How to use the webcam test
Press Start camera and allow the camera when your browser asks. Your picture appears straight away, with the camera's name, the resolution it's sending and how many frames a second actually arrive. If you have more than one camera, pick the one to test from the list; their names appear once you've allowed the camera.
The picture never leaves your device. Save a photo downloads a still to your computer if you want to compare cameras or settings.
Why the frame rate drops
Webcams slow down in dim light, keeping the shutter open longer on each frame to gather more light. A camera that manages 30 frames a second by a window can drop to 15 in a dark room, which makes video calls look jerky. Light in front of you, not behind, fixes it.
Resolution
The test starts at 1080p, the same as most video call apps, and shows the highest resolution your camera supports alongside. Pick Highest it offers to try the camera at its best. Some built-in cameras, including Macs', zoom in at their highest settings because they crop the sensor, so if the picture suddenly looks closer, that's why.
Common questions
Why is my webcam showing a black screen?
Usually something is covering the lens: a privacy shutter, a sticker or a laptop's camera switch. If the camera light is on but the picture stays black, the camera is sending nothing and has probably failed. If the browser shows an error instead, the camera is blocked or in use by another app.
Is it safe to allow the camera on this site?
Yes. The picture is shown on your screen by your own browser and isn't recorded or uploaded. You can turn the camera off at any time, and closing the page turns it off too.
Why does my 1080p webcam only show 720p?
Some cameras only send their full resolution over a USB 3 port, or at a lower frame rate. Try another port and close other apps using the camera. Cheap webcams sometimes advertise a resolution they upscale to rather than really capture.
Does the webcam test work on a phone?
Yes. Phones offer their front and back cameras, and you can switch between them from the camera list.