Quick check: Run the related device test and keep it open while trying these steps.
Check what the browser sees
Open the webcam test and click Start camera. If the picture appears, the browser has access. The resolution appears beneath the preview once the stream starts. If a different camera appears, use the camera selector to choose the one you intend to use. The preview is mirrored like many video-call previews; mirroring alone is not a fault.
Look at the camera itself
Open a built-in privacy shutter or remove a lens cover. Check for a camera-disable key on a laptop keyboard and reconnect an external webcam. For USB cameras, try a direct port instead of a hub. A black picture with an active camera can simply be a covered lens, while a permission error points to a different cause.
Allow access in both places
In Windows 11, open Settings → Privacy & security → Camera. Allow camera access and access for desktop apps, which includes many browsers. Then inspect the permission control beside the address bar and allow the camera for this site. Reload after changing permissions. Only grant access to a site when you intend to use its camera tool.
Compare with another app
Close video meetings and camera software, then retry. If Windows Camera also fails, the issue is likely outside this website. If Windows Camera works but this test fails, recheck the browser permission and device selection. If the test works but a meeting app fails, choose the camera inside that app. This page shows a live image locally; it does not upload your camera feed.
After each change, test the device again. Change one setting at a time so you can identify what helped.
Further reference: Official device or browser documentation ↗