About AudioTest Pro
A bench of audio test instruments that fits in a browser tab.
How the tools work
Every tone, sweep and noise on this site is synthesised live on your device with the Web Audio API, the same audio engine browsers use for games and music apps. Oscillators run on your sound card's clock, so frequencies are accurate to a small fraction of a hertz. A gentle limiter sits at the end of the chain so that no tool can send a full-scale spike to your speakers, and every tool starts at a low level (−30 dBFS by default).
The microphone tools read your input through the same API and analyse it with a Fast Fourier Transform. Audio is processed in memory and is never uploaded.
The troubleshooting assistant on the mic, speaker, headphone and subwoofer pages is the only feature that talks to a server. It sends the text you type (and, on the mic test, the numeric readings) to an AI language model through Vercel AI Gateway and streams back suggested steps. It is instructed to stay on audio-equipment topics and never to give medical advice.
What uncalibrated testing means
A hardware audio analyzer knows exactly how loud its output is. A browser does not: your volume setting, amplifier, speakers or headphones, and the room all change the level that reaches your ears. That is why our hearing tools compare your ears with each other and across frequencies instead of reporting hearing levels in dB HL, and why microphone readings are in dBFS rather than dB SPL.
Hearing health sources
- World Health Organization: World report on hearing (2021) and the Make Listening Safe initiative, including the global safe-listening standard for personal audio devices.
- American Speech-Language-Hearing Association (ASHA): guidance on hearing screening, types of hearing loss and noise exposure.
- National Institute on Deafness and Other Communication Disorders (NIDCD, US National Institutes of Health): fact sheets on age-related hearing loss, noise-induced hearing loss and sudden deafness.
- NHS (UK): advice on hearing tests and when to see a GP about hearing loss.
Technical references
- ISO 16: standard tuning frequency (A4 = 440 Hz).
- ITU-T Recommendations Q.23 and Q.24: DTMF frequencies and receiver tolerances.
- W3C Web Audio API specification.
Nothing on this site is medical advice. If you have any concern about your hearing, see an audiologist or doctor.