About SoundTester

Free, local-first audio checks and reference tones for anyone who needs a quick answer.

SoundTester is an independent static site with no affiliation to any audio hardware vendor.

SoundTester exists because the questions are simple and universal: is the left channel actually the left channel, does this speaker reproduce bass, can I hear this frequency, is my microphone working? A plain browser page can answer all of them in seconds — without an install, and without sending your audio anywhere.

Every tone you hear is synthesized on your device by the Web Audio API, the audio engine built into Chrome, Edge, Firefox, and Safari. Microphone tools use getUserMedia and analyze the stream locally; recordings stay in the page memory until you close or discard them. There is no account, no cloud storage, and no upload path in the code.

Honesty about limits: browser output is not calibrated lab equipment. Volume depends on your device and OS settings, and headphones vary widely. Hearing-related pages on this site are screening aids, never medical devices, and say so clearly on the page.

FAQ

Who is SoundTester for?

Anyone who needs a quick answer before a call, after buying headphones, or while setting up speakers — plus audio hobbyists who need a reference tone, noise color, or sweep on hand.

What technology does it use?

Plain static pages plus the Web Audio API and, for microphone tools, getUserMedia. There is no server-side audio processing at all.

How is it funded?

The site is static and cheap to host. If advertising or analytics are ever added, the privacy policy will be updated first and the local-audio promise stays unchanged.