“Frequency generator” covers three genuinely different tools that happen to share a name — a bench instrument for electronics, a hardware unit that also emits an electromagnetic field, and software that synthesizes a tone. Picking well starts with working out which one you were actually looking for.
One of the picks below is ours, and it says so. Facts about other products are taken from their own pages, verified 29 August 2026 and linked.
Read this before you buy anything
Below about 20 Hz, you cannot hear a tone at all, and no headphone or speaker reproduces one. So when a product offers 7.83 Hz or a “delta” frequency through audio, what reaches your ears is either a binaural beat — two tones a few Hz apart, one per ear, where you perceive the difference — or an isochronic pulse, a tone switched on and off at that rate. Both are useful. Neither is the raw frequency.
Above about 20 kHz you also cannot hear anything, and standard digital audio cannot even carry it. Hardware can emit those frequencies as a physical field; that is a real difference between the categories, and it is worth knowing which one you are paying for.
Best free tone generatorOurs
HiveJournal Frequencies
HiveJournal — ours · Free
Pure sines, binaural beats and isochronic pulses generated in the browser at exact frequencies, with the peer-reviewed research shown beside each preset — including the systematic review that questions whether binaural beats do anything at all, and an explicit "no study we could find" wherever that is the truth.
Best for. Anyone who wants to try tones before buying anything, and wants to see the evidence next to them.
Open it →Best hardware unit with PEMF output
Bio-Healing Frequency Generator V2
Calminity · See listing
A standalone handheld device outputting audible sine waves and a pulsed electromagnetic field, with a stated range of 0.01 Hz to 100,000 Hz. Ships with earphones, a case and printed frequency guides, a one-year warranty and a stated 60-day money-back guarantee. The PEMF and ultrasonic output are things no software can reproduce.
Best for. Someone who specifically wants a physical device and the electromagnetic output, and wants it to work with no phone or connection.
View the vendor’s page →Best for lab-grade signal work
A bench function generator
Various instrument makers · Varies widely
If the reason you want a frequency generator is electronics testing rather than listening — calibrating equipment, sweeping a circuit, driving a transducer — a laboratory function generator is the actual tool for that job, with calibrated output, an oscilloscope-friendly signal and specified accuracy.
Best for. Engineering and test work, where an audio tone is not what you needed at all.
About health claims
Several products in this category are marketed with claims about pain, sleep or wellbeing. We do not repeat those claims and we do not argue against them — we describe what each tool does and link the vendor so you can read their wording yourself.
We make no claims about what these tones do. Where peer-reviewed research exists we link it, with its limitations shown next to it.
Product names and trademarks belong to their owners. We are not affiliated with, endorsed by, or partnered with any other vendor named on this page.