Webcam Test
Click start and allow camera access. You'll see a live preview with the camera's actual resolution and frame rate.
What this test checks
The preview is mirrored, like looking in a mirror — that's how every video app shows you to yourself, while others see the unmirrored image (the snapshot shows what you see). If the preview is black, check for a physical privacy shutter first, then whether another app holds the camera, then the browser permission.
Compare the reported and measured frame rates. A camera that claims 30 fps but measures far lower usually means poor lighting — most webcams halve their frame rate in dim rooms to brighten the image. If the resolution reads lower than the box promised, the camera may be connected to a USB 2.0 port that can't carry the full bandwidth.