Webcam and microphone test

What it does

It opens the camera and the microphone and shows what arrives. The video preview tells you whether the camera is framing you and whether the image is sharp. The level bar tells you whether the microphone is picking up, and how loud.

Use it before a stream, a meeting or a recording, when the only question is “does it work?”.

What it shows about the camera

• Resolution in pixels, with the common name where one exists (720p, 1080p, 4K).
• Aspect ratio, reduced: 16:9, 4:3, 16:10.
• Frames per second as declared by the video track.

The resolution is what is actually arriving, read off the video element. It is not what the camera claims to produce: the two diverge when the browser crops or rescales, which is exactly when the number matters.

The preview is mirrored by default, like a mirror. The switch straightens it. It changes this page only: whoever watches you always sees the unmirrored image.

What it shows about the microphone

A bar that follows the level, with a peak marker. The scale is in decibels rather than in amplitude, so normal speech occupies the middle of the bar instead of being squashed at the bottom.

At full scale the clipping warning appears. A signal that reaches the maximum sounds distorted, and the fix is to turn the gain down in your system settings.

The browser’s three filters — echo cancellation, noise suppression and automatic gain — are requested off. They exist for phone calls. Here they falsify the measurement: automatic gain in particular pulls any level back to the middle, which means it answers “fine” even to a badly set microphone.

About permissions

Camera and microphone are turned on separately, with two distinct permissions. Anyone who only wants to test the microphone does not also switch the camera on.

Device names are empty until permission is given: that is a browser defence against fingerprinting, not an error. After consent the list is rebuilt with the real names.

When something will not open, the message says which cause it is: permission denied, no device, the device held by another program, an insecure connection, a browser that does not expose access.

What is not here

It does not record. There is no record button, no file is written, no frame is sampled. The tool shows, and that is all.

It does not test your speakers. That would mean playing a sound, and this tool plays none: the microphone is never routed back to the speakers, or it would howl.

The camera stays on until you press Stop, even if you switch tabs. Switching it off by itself would mean asking for the permission again on your return, and losing the device you chose.

About your data

Video and audio stay in your browser. This site is made of static files and has no server to send anything to, even if it wanted one.