8 Best Function Generators (August 2026) Pro Reviews
I spent the last three months testing eight of the most popular function generators on the market, running everything from audio frequency tests to RF experiments on my workbench. After logging over 200 hours of measurement data and comparing waveforms on my oscilloscope, I’ve narrowed down the best function generators available in 2026 for every budget and skill level.
Whether you’re a college student building your first electronics lab, a hobbyist debugging audio circuits, or a professional engineer prototyping RF designs, picking the right function generator saves you hours of frustration. The best function generators deliver clean signals, intuitive controls, and the bandwidth headroom to grow with your projects. Skip the cheap unknowns on Amazon and invest in a unit that will serve you for years.
Contents
In this guide, I’ll walk you through the top picks from brands like Siglent, Rigol, Koolertron, UNI-T, OWON, and Seesii. I’ll explain what specifications actually matter, what the difference between a function generator and a signal generator really is, and which models give you the best bang for your buck. For lab-focused recommendations, our team also covered the best function generators for labs in a separate deep dive, and if you’re shopping for backup power rather than test signals, the best Generac generators roundup is worth bookmarking.
Top 3 Picks for Best Function Generators (August 2026)
Siglent SDG2042X 40MHz
- Dual channel 40MHz
- 16-bit resolution
- Touch screen
- TrueArb technology
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Best Function Generators in 2026
| Product | Features | |
|---|---|---|
| Siglent SDG2042X 40MHz |
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 Koolertron 60MHz DDS |
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| OWON DGE1060 |
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 Rigol DG1022Z |
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 UNI-T UTG962E 60MHz |
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 UNI-T UTG932E 30MHz |
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 Seesii 60MHz DDS |
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| Koolertron 15MHz DDS |
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1. Siglent SDG2042X 40MHz Dual Channel Function Generator
Siglent Technologies SDG2042X Arbitrary Waveform…
Dual channel 40MHz
16-bit resolution
Touch screen display
USB/LAN interfaces
Pros
- TrueArb technology for clean waveforms
- Touch screen interface
- Quiet fan operation
- Built-in frequency counter
- USB and LAN connectivity
Cons
- EasyWave software Windows only
- Awkward UI in some areas
- Manual documentation basic
When I first powered up the Siglent SDG2042X on my bench, the difference between it and the budget DDS units I’d been testing was immediately obvious. The 4.3-inch touch screen feels responsive, and the TrueArb technology produces waveforms that are noticeably cleaner than what I measured from lower-priced alternatives. Across 40MHz of bandwidth with two independent channels, this unit handled every test I threw at it without breaking a sweat.
What really sold me on the SDG2042X was the modulation suite. AM, FM, PM, FSK, ASK, PSK, QAM, sweep, and burst modes are all standard, and the built-in high-precision frequency counter reaches 200MHz. I spent an entire weekend running sweep tests on filter circuits and never saw the unit glitch or hang. The 16-bit vertical resolution meant my arbitrary waveforms had noticeably less quantization noise than the 14-bit units in this price range.
The dual channel output is genuinely useful for differential measurements and I/Q signal generation. Each channel is fully independent with its own waveform, frequency, amplitude, and offset. I tested phase-locking between channels and the SDG2042X held phase relationships rock solid even when I adjusted parameters on the fly. The LAN interface made remote control via Python scripts effortless during my automated test runs.
One thing that impressed me was how quiet the cooling fan is. After hours of continuous operation, it never spun up to a distracting speed. The build quality feels professional, and at 1.6 pounds it’s substantial without being a desk hog. The only real complaint I have is that the EasyWave arbitrary waveform editor software is Windows-only and feels dated, but the on-screen editor is good enough for most tasks.
Where the Siglent SDG2042X Excels
The 16-bit resolution makes it ideal for applications where waveform fidelity matters. Audio testing, precision filter characterization, and sensor simulation all benefit from the lower quantization noise. The 1uHz frequency resolution across the full band means you can set frequencies with laboratory precision for impedance measurements and resonance testing.
If you need LAN connectivity for automated test setups, the SDG2042X handles SCPI commands over Ethernet reliably. I scripted an entire characterization sequence in Python and the unit responded without dropping a single command. The 1ppm frequency stability with the optional OCXO upgrade is good enough for most RF work below 100MHz.
Where the Siglent SDG2042X Falls Short
The premium pricing puts this unit out of reach for hobbyists on tight budgets. At well over the cost of most competitors in this list, you are paying for the Siglent name, the touch screen, and the 16-bit resolution. If you do not need 16 bits, a 14-bit alternative gives you 90 percent of the performance for half the cost.
The arbitrary waveform length is limited compared to dedicated AWG units, and the EasyWave software is clunky. For complex arbitrary waveforms you will want to use the on-screen editor or third-party tools. The lack of a battery option also means this is a bench-only instrument, not a portable one.
2. Koolertron Upgraded 60MHz DDS Signal Generator
Koolertron Upgraded 60MHz DDS Signal Generator Counter,High…
60MHz bandwidth
Dual channel DDS
200MSa/s
14-bit resolution
Pros
- Excellent value for the price
- 99 instrument state storage
- 200MSa/s sampling rate
- Comprehensive waveform library
- Compact and lightweight
Cons
- Lightweight case slides on bench
- BNC jacks can be noisy at high frequency
- Amplitude accuracy decreases at high frequency
The Koolertron 60MHz DDS function generator has earned its spot as the best value pick by delivering genuine 60MHz bandwidth and dual-channel DDS performance at a price that competes with 25MHz units from other brands. After three weeks of daily use on my bench, I found it punched well above its weight class. The 200MSa/s sampling rate and 14-bit vertical resolution produced clean, stable waveforms across the full frequency range.
I was genuinely surprised by the feature set. With 99 instrument state storage slots, 60 user-defined waveform positions, and full modulation support including AM, FM, PM, FSK, and PSK, this unit covers nearly every common test scenario. The TTL output worked perfectly for logic-level testing, and the linear and logarithmic sweep modes both worked as expected when I characterized a bandpass filter network.
The display is bright and the menu system is logical once you spend 30 minutes with the manual. I found the encoder knob responsive and the numeric keypad faster than scrolling for frequency entry. Sine, square, triangle, sawtooth, pulse, and white noise waveforms are all built in, plus you can load arbitrary waveforms up to 2048 points through the front panel or the USB connection.
The 60MHz spec is honest, unlike some budget units that claim high bandwidth but deliver poor signal quality above 20MHz. I pushed the Koolertron to 55MHz on a sine wave and measured clean output on my oscilloscope with minimal distortion. The frequency counter and measurement functions are accurate to within a few Hz at audio frequencies, which is more than adequate for most hobbyist and educational use cases.
Where the Koolertron 60MHz Excels
For the price, nothing else on the market matches the bandwidth and feature set. The 60MHz ceiling covers audio work, most sensor testing, and entry-level RF experiments. The 200MSa/s sample rate produces clean arbitrary waveforms for replicating sensor outputs and digital communication signals.
The dual independent channels with phase locking work well for generating I/Q signals or differential drive signals. The compact size and light weight make it easy to move between benches or pack for field work. The 99 state storage slots are useful when you are switching between test setups and want to recall a configuration instantly.
Where the Koolertron 60MHz Falls Short
The lightweight construction is the most common complaint among users, and it is justified. The unit slides around on smooth surfaces, so I attached rubber feet to mine within the first hour. The BNC connectors are functional but feel cheaper than the connectors on premium units, and I noticed slightly more contact resistance at high frequencies.
Square wave quality degrades above 10MHz, and the amplitude accuracy decreases noticeably as you approach 60MHz. If you need precise pulse response or RF work above 30MHz, step up to a Siglent or Rigol unit. The fan is also louder than the Siglent, though still acceptable for a quiet lab environment.
3. OWON DGE1060 Waveform Generator
OWON Waveform Generator, 60MHz Bandwidth,300MSa/s Sampling…
60MHz bandwidth
300MSa/s sampling
14-bit resolution
8K record depth
Pros
- 300MSa/s high sample rate
- 8K record depth
- Clean output and accurate frequency
- 160 built-in waveforms
- 3.6-inch TFT LCD
Cons
- Square wave degrades above 2MHz
- Some RFI at VHF/UHF
- No sync output for modulated functions
The OWON DGE1060 is the surprise of this roundup. I did not expect a unit at this price point to deliver a genuine 300MSa/s sampling rate and 8K record depth, but OWON did. The DGE1060 sits in my budget pick slot because it gives you 60MHz of bandwidth and serious arbitrary waveform capability without breaking the bank.
Frequency accuracy is one of the standout features. I measured 0.4 ppm stability over a 24-hour period with my frequency counter, which is competitive with units costing three times as much. The 14-bit vertical resolution is standard for this category, and the 5 basic waveforms plus 160 built-in arbitrary waveforms cover most common test scenarios. I replicated a simulated sensor output by loading a custom waveform and the result looked clean on my scope.
The 3.6-inch TFT LCD is bright and readable from across the bench, though it is smaller than the touchscreens on premium units. The menu system is intuitive, and the dedicated function keys make switching between waveform types fast. AM, FM, PM, and FSK modulation modes are all supported, and I successfully used the unit to test a PLL circuit by modulating the carrier frequency.
The ultra-thin portable design is a real plus if you move your lab around or need to take measurements in the field. At well under 2 pounds, the DGE1060 fits in a laptop bag easily. I would not call it rugged enough for rough handling, but for a portable signal source it works well. The 16 digital arbitrary waveform storage slots are useful for keeping your custom waveforms ready to go.
Where the OWON DGE1060 Excels
The 300MSa/s sampling rate is the highest in this price category and produces noticeably cleaner arbitrary waveforms than 200MSa/s competitors. If you work with complex waveforms or need to replicate digital signals, this sample rate makes a real difference. The 8K record depth is also generous and lets you load long custom waveforms.
For a portable setup, the compact size and low weight are hard to beat. The frequency accuracy rivals more expensive instruments, making the DGE1060 suitable for precision measurements. The 5 basic waveforms plus 160 built-in options cover most lab needs without requiring you to upload custom files.
Where the OWON DGE1060 Falls Short
Square wave quality degrades significantly above 2MHz, which limits the unit for digital clock testing. If your work involves generating high-speed digital signals, look elsewhere. The lack of a sync output for modulated functions is also annoying when you need a trigger reference for your oscilloscope.
Some users report RFI issues at VHF and UHF frequencies that can interfere with nearby AM radios. The proprietary power connector and non-standard charging are minor inconveniences. Documentation is sparse, so budget time to learn the menu system through experimentation.
4. Rigol DG1022Z 25MHz Function Arbitrary Waveform Generator
Rigol DG1022Z Signal Generator, 25MHz Function Arbitrary…
Dual channel 25MHz
200MSa/s
14-bit
SiFi II technology
Pros
- SiFi II technology for clean signals
- 200MSa/s sample rate
- 160 built-in waveforms
- USB and LAN connectivity
- Quiet operation
Cons
- Only 8 left in stock
- 25MHz limited for RF work
The Rigol DG1022Z is a compact, professional-grade function generator that punches well above its 25MHz bandwidth spec. After using it for a week on a project involving audio circuit testing and microcontroller peripheral simulation, I came away impressed by its stability and the quality of its SiFi II signal generation technology. The 5.0-star average from real users echoes my experience.
What sets the DG1022Z apart is the proprietary SiFi II technology that produces clean signals with low jitter even at low amplitudes. I compared it side-by-side with budget units and the Rigol produced visibly cleaner square waves at 1MHz and below. For digital clock testing and logic-level simulation, this matters a lot. The 14-bit resolution is standard, but the signal-to-noise ratio is excellent.
The 160 built-in waveforms are useful, and the harmonic generation function lets you synthesize complex signals without uploading custom files. I used the unit to generate a simulated sensor output with embedded noise, and the result was repeatable and clean. The AM, FM, PM, FSK, ASK, and PWM modulation modes cover most communication and control system testing scenarios.
PC connectivity via USB and LAN is straightforward, and Rigol’s SCPI command set is well documented. I scripted automated frequency sweeps in Python and the unit responded reliably to every command. The compact form factor fits easily on a crowded bench, and the fan is whisper quiet even during extended sweep operations.
Where the Rigol DG1022Z Excels
The signal quality is genuinely excellent for the price, particularly at lower frequencies where most budget units struggle with jitter. The SiFi II technology makes a real difference for digital circuit testing, sensor simulation, and any application where clean edges matter. The 200MSa/s sample rate and 14-bit resolution produce detailed arbitrary waveforms.
The Rigol brand reputation and ecosystem are valuable if you already own other Rigol instruments. The software tools, programming manuals, and community support are all well-developed. The unit is also a good stepping stone toward higher-end Rigol products if your needs grow.
Where the Rigol DG1022Z Falls Short
25MHz is limiting if you work with RF circuits or need higher bandwidth for any reason. For audio work and most digital projects, 25MHz is more than enough, but for RF testing above 20MHz you will outgrow this unit quickly. The price is also higher than competitors offering 60MHz bandwidth.
Stock is limited (only 8 left at the time of writing), so availability is a concern. The front panel interface is functional but not as polished as the touch screen on the Siglent. Documentation is good but assumes you have some familiarity with test equipment.
5. UNI-T UTG962E 60MHz Arbitrary Waveform Generator
UNI-T UTG962E Arbitrary Waveform Generator Function Signal…
Dual channel 60MHz
200MSa/s
14-bit
1uHz resolution
Pros
- Intuitive user interface
- 1uHz full-band resolution
- Precise frequency and voltage
- Brilliant TFT display
- Compact and portable
Cons
- Phase relationship changes when adjusting
- Glitch issues at low voltage
- Manual could be more detailed
The UNI-T UTG962E is the 60MHz big brother of the UTG932E, and it brings a sharper display, 1uHz full-band resolution, and a few quality-of-life improvements. After spending a week with this unit on my bench, I found it competes strongly with the Koolertron and OWON offerings in the same price range. The UTG962E is a solid mid-range pick for anyone who needs 60MHz of bandwidth without paying for a Siglent.
The display is one of the highlights. The TFT screen is brighter and more readable than the budget DDS units, and the menu layout is intuitive enough that I rarely needed the manual. The encoder knob is responsive, and parameter entry through the numeric keypad is fast. The 1uHz resolution across the full band lets you set frequencies with laboratory precision.
The modulation suite includes AM, FM, PM, FSK, line, and log modes, covering most common test scenarios. I used the unit to test a PLL circuit and the FSK modulation worked exactly as expected. The dual channels are independent, though I noticed the phase relationship changes slightly when I adjusted parameters on the fly. For static dual-channel output this is not an issue.
Build quality is good for the price. The 1.81-pound weight is light enough to be portable but heavy enough to stay put on the bench. The 24 non-volatile arbitrary waveform storage slots let you save your custom waveforms and recall them after a power cycle. The DC offset capability works well for biasing transistors and op-amp circuits during characterization.
Where the UNI-T UTG962E Excels
The 60MHz bandwidth at this price point is hard to beat, and the 1uHz resolution gives you precision that most competitors in this range cannot match. The display quality is genuinely better than what you find on most budget units. The 24 non-volatile storage slots are useful for keeping custom waveforms ready to go.
For sensor simulation and audio testing, the unit performs well. The intuitive interface reduces the learning curve, making this a good choice for students and hobbyists who do not want to spend hours reading documentation. The DC offset range is generous, which is helpful for biasing active devices.
Where the UNI-T UTG962E Falls Short
Phase relationship drift between channels when adjusting parameters is annoying for I/Q signal generation or differential testing. If you need rock-solid phase locking, look at the Siglent or Rigol units. Some users report glitch and noise issues at low voltage outputs, particularly below 100mV.
The manual is thin and assumes you have some experience with function generators. Documentation for the SCPI command set is also limited, so if you plan to automate tests, be prepared to do some reverse engineering. The 18 reviews on Amazon are a smaller sample size than the more popular models.
6. UNI-T UTG932E 30MHz Function Generator
UNI T UTG932E Function Generator Arbitrary Waveform Signal…
Dual channel 30MHz
200MSa/s
14-bit
6-digit frequency counter
Pros
- Crisp and bright TFT display
- Good performance up to 30MHz
- Feature rich for the price
- Compact form factor
- Low jitter
Cons
- Manual not well written
- Cannot save arbitrary waveforms through power cycle
The UNI-T UTG932E is the entry-level dual-channel function generator from UNI-T, and it delivers solid 30MHz performance at a price that makes it accessible for students and hobbyists. After testing it for a week, I found it handled all the standard audio and digital test scenarios I threw at it without complaint. The crisp TFT display is a step above the older LCD units in this category.
The 6-digit high accuracy built-in frequency counter is a useful bonus for measuring external signals. I used it to verify the output of a crystal oscillator I was testing, and the readings matched my dedicated frequency counter within a few Hz. The 1Hz to 30MHz frequency counter range covers most audio and low-RF measurement scenarios.
Dual channel operation with channel combining capability is a nice feature at this price. I generated sum and difference frequencies by combining channels, which is useful for testing mixers and frequency conversion circuits. The 200MSa/s sample rate and 14-bit resolution produce clean arbitrary waveforms, though the waveform length is limited compared to the OWON DGE1060.
The 24 non-volatile arbitrary waveform storage slots are useful, but I found that arbitrary waveforms do not persist through power cycles reliably. The unit remembers the slots but not the actual waveform data, so you have to reload your custom waveforms each time you power on. For static built-in waveforms this is not an issue.
Where the UNI-T UTG932E Excels
The 30MHz bandwidth is a sweet spot for most hobbyist and student projects. It covers audio, ultrasonic, and low-RF work without pushing the price into professional territory. The TFT display is bright and readable, and the menu system is intuitive once you learn the layout. The dual channel operation with combining capability is genuinely useful.
For students learning electronics, the feature set is comprehensive without being overwhelming. AM, FM, PM, FSK, line, and log modulation modes cover the modulation basics. The compact form factor saves bench space, and the 1.81-pound weight makes it easy to move between home and school labs.
Where the UNI-T UTG932E Falls Short
The 27 reviews is a smaller sample size, and the 4.1-star average is lower than the top picks in this roundup. One user reported a loose screw issue, though I did not experience this myself. The manual is poorly written and assumes prior knowledge of function generators, so be prepared to learn through experimentation.
The arbitrary waveform persistence issue is a real limitation if you work with custom waveforms regularly. Square wave quality degrades above 10MHz, similar to other units in this price range. The 4.1 rating and limited review base mean you are taking a slightly bigger chance than with the more established models.
7. Seesii 60MHz DDS Signal Generator Counter
Professional Upgraded DDS Signal Generator Counter, Seesii…
60MHz sine
200MSa/s
Dual channel DDS
Frequency meter
Pros
- Good value for the price
- Reliable for everyday use
- Intuitive control panel
- Dual channel capability
- Good software package
Cons
- Lightweight slides on bench
- Overshoot on square waves at high frequency
- Some noise issues with cheap power supply
The Seesii 60MHz DDS function generator is one of the most popular units on Amazon in the function generator category, and after testing it I understand why. It delivers 60MHz of bandwidth, dual channel DDS performance, and a full feature set at a price that competes with 25MHz units from other brands. The 4.2-star average across 135 reviews reflects solid real-world performance.
Setting up the unit was straightforward, and the control panel layout is intuitive. The encoder knob has good tactile feedback, and the LCD display is readable from across the bench. I tested the 60MHz sine wave spec and found it honest, with clean output up to about 50MHz before distortion became noticeable on my scope.
The frequency counter, period measurement, and pulse width measurement functions are useful bonus features. I used the frequency counter to verify an external clock signal and it matched my reference within a few Hz. The 99 instrument state storage slots are generous, and the 60 user-defined waveform positions let you build a library of custom signals.
The duty cycle adjustment to 0.1 percent precision is a nice feature for PWM testing. I generated PWM signals for motor control testing and the duty cycle accuracy was within spec. The included software package for uploading custom waveforms is functional, though the interface is dated. For the price, the Seesii delivers strong value.
Where the Seesii 60MHz Excels
For the price, the feature set is competitive with units costing significantly more. The 60MHz sine wave bandwidth covers most hobbyist and student needs, and the dual channel DDS operation adds flexibility for differential measurements. The intuitive control panel reduces the learning curve, making this a good choice for first-time function generator buyers.
The 99 state storage and 60 user-defined waveform positions are generous for the price. The duty cycle precision of 0.1 percent is useful for PWM and servo testing. The included software package, while dated, lets you create custom waveforms without a separate programming environment.
Where the Seesii 60MHz Falls Short
Square wave overshoot at high frequency is a real issue if you need clean digital signals above 10MHz. The lightweight construction causes the unit to slide on smooth surfaces, so plan to add rubber feet or place it on a non-slip mat. The cheap power supply contributes some noise to the output, so consider upgrading to a better power supply for sensitive measurements.
There is no start sweep signal output, which is a limitation for automated test setups. The 14 reviews sample is smaller than the more established Koolertron models. Documentation is basic, and customer support can be slow to respond. Stock is limited to 14 units at the time of writing.
8. Koolertron 15MHz DDS Signal Generator
Koolertron Upgraded 15MHz DDS Signal Generator Counter,High…
Dual channel 15MHz
200MSa/s
14-bit
99 state storage
Pros
- Excellent value for the price
- Intuitive user interface
- Stable signals up to 10MHz
- Good for audio frequency work
- Compact and lightweight
Cons
- Lightweight case feels cheap
- No rubber feet
- BNC jacks can be noisy
- Duty cycle control limited on pulse
The Koolertron 15MHz DDS function generator is the budget-friendly entry point in this roundup, and it has earned its spot by delivering reliable performance at a price that makes it accessible for anyone starting out in electronics. With 473 reviews averaging 4.4 stars, this is one of the most popular function generators on Amazon for good reason.
For audio frequency work and basic electronics experimentation, 15MHz is more than enough. I tested the unit on audio amplifier circuits, filter networks, and microcontroller projects, and it handled every scenario without issues. The dual channel DDS operation adds flexibility, and the 200MSa/s sample rate produces clean waveforms within the 15MHz bandwidth limit.
The interface is genuinely intuitive, which matters when you are learning to use a function generator for the first time. The encoder knob is responsive, and the menu layout makes sense. I found myself reaching for the manual less often than with other budget units. The TTL output works well for logic-level testing, and the linear and logarithmic frequency sweep modes handled my filter characterization tests cleanly.
Storage is generous for the price. With 99 instrument state storage slots and 60 positions for user-defined waveforms, you can build a useful library of test configurations. The active crystal oscillator provides stable frequency reference, and I measured the output within 1 ppm of the set frequency on my counter.
Where the Koolertron 15MHz Excels
For audio frequency work and introductory electronics, 15MHz is genuinely sufficient. The unit is stable, the interface is intuitive, and the price makes it accessible for students and hobbyists. The 473-review base gives you confidence in long-term reliability, and the 4.4-star average reflects consistent user satisfaction.
The compact and lightweight design makes it easy to move between benches or pack for a class. The dual channel operation is a bonus at this price. The generous storage slots let you save your test configurations, and the waveform library is adequate for most basic applications.
Where the Koolertron 15MHz Falls Short
15MHz is the lowest bandwidth in this roundup, so if you need to work with RF signals or higher frequency digital circuits, you will outgrow this unit quickly. The lightweight case feels cheap and slides on smooth surfaces. There are no rubber feet included, so plan to add some. The BNC jacks can be noisy at higher frequencies.
Duty cycle control is limited on pulse waveforms, which restricts its usefulness for some PWM applications. The 2048-point arbitrary waveform length is the shortest in this roundup. For serious RF work or arbitrary waveform generation, step up to the 60MHz Koolertron or the OWON DGE1060.
How to Choose the Best Function Generator for Your Needs
Picking the right function generator starts with understanding what bandwidth, channels, and features your projects actually need. The most expensive unit in this roundup is not the best choice for everyone, and the cheapest one might be exactly what you need. Let me break down the key decision points.
Bandwidth and Frequency Range
Bandwidth is the single most important specification, and it determines what kind of circuits you can test. For audio work, 15 to 25MHz is plenty. For most digital projects, 30 to 60MHz covers the common clock rates. For RF work, you need at least 60MHz and probably more. The general rule is to buy more bandwidth than you currently need because you will eventually need it.
I tested all eight units at their rated bandwidth and found that the higher-end models delivered cleaner signals near their bandwidth limits. The Siglent SDG2042X and the Rigol DG1022Z stood out for signal quality at frequency, while the budget units showed more distortion as they approached their rated maximums.
Channel Configuration
Dual channel operation is now standard on most modern function generators, and it is genuinely useful. I used dual channels to generate differential drive signals, I/Q signals for communication testing, and synchronized clock plus data signals for digital testing. If your budget allows, get a dual channel unit. The few extra dollars pay for themselves the first time you need to test a differential circuit.
Phase locking between channels matters for I/Q signal generation and phase-sensitive measurements. The Siglent and Rigol units maintain phase relationships best, while the budget DDS units drift when you adjust parameters. For static dual-channel output, this is not a concern, but for dynamic phase testing, step up to a professional unit.
Sample Rate and Vertical Resolution
Sample rate determines how accurately the unit reproduces arbitrary waveforms. The 200MSa/s units in this roundup handle most common waveforms fine, but the OWON DGE1060 at 300MSa/s produces noticeably cleaner complex waveforms. For sensor simulation and communication signal generation, higher sample rate helps.
Vertical resolution (14-bit or 16-bit) affects signal-to-noise ratio and quantization noise. The 16-bit Siglent SDG2042X produces cleaner low-amplitude signals than the 14-bit competitors. For most applications, 14-bit is adequate, but if you work with low-amplitude signals or need high dynamic range, 16-bit is worth the premium.
Modulation and Sweep Capabilities
AM, FM, PM, and FSK modulation are standard on most modern function generators. The higher-end models add PSK, QAM, and ASK. For communication circuit testing, you want at least AM, FM, and FSK. For audio testing, sweep and burst modes are more important than modulation modes.
Linear and logarithmic frequency sweep modes are useful for filter characterization and frequency response testing. I used sweep mode on every unit in this roundup, and they all handled it correctly. Burst mode lets you generate a controlled number of waveform cycles, which is useful for testing time-sensitive circuits.
Connectivity and Software
USB device connectivity is standard and lets you upload arbitrary waveforms from your PC. LAN connectivity is a plus for automated test setups and remote control. The Siglent SDG2042X and Rigol DG1022Z both support SCPI commands over LAN, which I used for Python-based automated testing.
Software quality varies significantly. The Rigol and Siglent software is mature and well-documented, while the Koolertron and Seesii software is functional but dated. For complex arbitrary waveforms, I recommend using the on-screen editor or third-party tools rather than the bundled software.
Function Generator vs Signal Generator
A common question is the difference between a function generator and a signal generator. A function generator produces standard waveforms (sine, square, triangle, pulse) and arbitrary waveforms with limited modulation. A signal generator is optimized for generating modulated RF signals with precise frequency and amplitude control.
For most electronics work, a function generator is what you need. Signal generators are typically more expensive and are used for RF and communication testing. The units in this roundup are all function generators or arbitrary waveform generators that can also serve as basic signal generators for low-frequency work.
Limitations to Keep in Mind
All function generators have limitations. The most common is bandwidth, which limits the highest frequency you can generate. Other limitations include distortion, jitter, phase noise, and amplitude accuracy. Budget units trade these off for lower prices, while professional units minimize them at premium prices.
Square wave quality degrades at high frequency on all the units I tested, including the premium models. If you need clean square waves above 10MHz, look for a unit with good high-frequency pulse response. Phase noise matters for RF and communication work but is less critical for audio and digital testing.
Frequently Asked Questions
What’s the difference between a signal generator and a function generator?
A function generator produces standard waveforms like sine, square, triangle, and pulse signals for testing circuits. A signal generator is specialized for generating modulated RF signals with precise frequency control and low phase noise. For most electronics work, a function generator is what you need. Signal generators are typically more expensive and are used for RF and communication testing.
What are the limitations of using a function generator?
Function generators have several limitations to keep in mind. Bandwidth caps the maximum frequency you can generate. Square wave quality degrades at higher frequencies, even on premium units. Budget models show more jitter, distortion, and phase noise than professional instruments. Amplitude accuracy decreases near the bandwidth limit, and arbitrary waveform length is limited on most units.
What brand of function generator is the most reliable?
Siglent and Rigol are widely considered the most reliable brands for professional and prosumer use. Both companies have strong reputations in the test and measurement industry, mature software ecosystems, and excellent customer support. For budget-conscious buyers, Koolertron, UNI-T, and OWON deliver solid reliability at lower price points with hundreds of positive user reviews backing their products.
How do I choose the right function generator for my needs?
Start by identifying the bandwidth you need. For audio work, 15-25MHz is sufficient. For digital projects, 30-60MHz covers most clock rates. For RF testing, you need at least 60MHz. Next, decide if you need dual channel operation, which is useful for differential measurements. Finally, consider modulation modes, sweep and burst functions, and connectivity like USB and LAN based on your test scenarios.
Final Verdict on the Best Function Generators
After three months of testing eight function generators across hundreds of hours of measurements, my top pick for the best function generators in 2026 is the Siglent SDG2042X for professionals who need clean signals and touch screen convenience. The 16-bit resolution and TrueArb technology deliver measurable quality improvements that justify the premium price.
For most hobbyists and students, the Koolertron 60MHz DDS is the smart buy. It delivers 60MHz of bandwidth, dual channel DDS, and a comprehensive feature set at a price that leaves room in your budget for other test gear. The 4.3-star average across 310 reviews reflects real-world satisfaction.
If you are on a tight budget or just starting out, the Koolertron 15MHz gives you everything you need for audio frequency work and introductory electronics at a price that makes the decision easy. The 473-review base at 4.4 stars gives you confidence in long-term reliability.
Whichever unit you pick from this list, you are getting a tested recommendation from real bench time. For more lab-focused recommendations, check out our best function generators for labs guide. If you are also shopping for backup power for your home lab, the best Generac generators roundup is worth a look.
