See your camera live, check the real resolution and frame rate, and save a snapshot. Nothing is uploaded.
To test your webcam online, press Start and allow the camera in the browser prompt: if the live picture appears, the camera works and the browser can use it. Below the picture the page lists the size the camera delivered, the size you asked for, and a frame rate counted over 2 seconds. The page asks for the camera only when you press Start, never when it loads. Stop, or leaving the page, switches the camera off, and a camera light, if it has one, should go out. If the picture stays black or the page shows an error, the message says why: the camera is blocked for this site, no camera was found, or another app or tab is already using it.
The resolution chips (480p, 720p, 1080p, 4K) are requests, not orders. The page asks the browser for an ideal width and height, and the browser picks the closest mode the camera offers. So you may ask for 1920 × 1080 and receive 1280 × 720, and the page shows both numbers and says which is which. A lower result usually means the camera cannot do the size you asked for, or the connection or another app limits it. The delivered size is read from the camera track's settings. If a camera reports its sides swapped, for example 720 × 1280 for a portrait picture, the page compares the long and the short edges, so it still counts as a match. Changing the chip restarts the camera with the new request.
Once the video is playing, the page counts frames for 2 seconds and divides by the time. Sixty frames in 2 seconds is 30.0 fps, and 59 frames is 29.5 fps. In browsers that support requestVideoFrameCallback, each count is a frame the camera really delivered. In others the page falls back to counting screen redraws while the video plays, which shows the screen's refresh rate rather than the camera's, and the page says so in a note instead of passing it off as the camera's rate. The rate can change with conditions such as lighting, so press Measure frame rate again after you change something. The track may also report a frame rate of its own, shown under the measured value.
Mirror the preview flips the picture left to right, as in a bathroom mirror, and starts on. Take snapshot copies the current frame to a canvas and shows it as a PNG at the full delivered size; the snapshot follows the mirror switch, so it looks like the preview. Download PNG saves it as a file named like snapshot-2026-10-15-1432.png. Nothing is saved until you press Download PNG. The snapshot and the video stay in this tab's memory and are gone when you close or reload the page. The test measures what the browser gives a web page; a video-call app can apply its own settings, filters and limits on top.
It asks only after you press Start. If you blocked this site earlier, the browser skips the prompt: click the lock icon in the address bar, set Camera to Allow, and press Start again. A page opened over plain http:// is not allowed to use the camera at all.
The camera is opened but sends no light. Check for a physical shutter or a privacy switch, then check whether another app or tab is using the camera: a camera is often used by one app at a time, and the page then shows a message that the camera is in use. Closing the other app and pressing Start again usually fixes it.
The chips ask for an ideal size, and the browser gives the closest mode the camera offers. Asking for 1920 × 1080 from a camera that tops out at 1280 × 720 gives 1280 × 720. The page shows both numbers so you can see the gap. A camera shared with another app or on a slow connection can also be limited.
Press Start and wait 2 seconds. The Frame rate tile shows frames counted over that time, for example 60 frames in 2 seconds gives 30.0 fps. If the note says the browser cannot count camera frames, the number is the screen's redraw rate and only a rough guide. Press Measure frame rate again after changing the light.
Yes. After you allow access, the Camera list shows each camera the browser reports, such as a built-in webcam and a USB camera, and choosing one restarts the preview with it. If a camera is plugged in later, the list updates by itself.
No. The video is processed in your browser and not uploaded. The page only shows the live picture and does not record it. A snapshot stays in this tab until you press Download PNG or leave the page. The page counts visits and presses of Start with Google Analytics, never pictures.