Webcam Low-Light Test
See a live brightness histogram with crushed-shadow and blown-highlight indicators. No AI, no face analysis, no recording.
The histogram shows how your camera exposes the current scene. In low light the graph bunches to the left and crushed-shadow percentage rises. This is a visual exposure aid — no AI, no face detection, and nothing is recorded.
How this test works
Camera tests request a video stream with getUserMedia and render it into a <video> element that stays entirely on your device. We read the track’s real settings — resolution, aspect ratio, frame rate and facing mode — directly from the MediaStreamTrack.
Where the browser supports it, we estimate delivered frame rate with requestVideoFrameCallback, which fires once per painted frame. Snapshots are drawn to an in-memory canvas and offered as a local download; nothing is sent to a server.
The camera is opened only when you click, an on-screen indicator shows when it is active, and the stream is stopped the instant you press Stop, leave the page, or switch tabs.
How to use it
- Press the grant-access button and allow camera access when your browser asks.
- Check the live preview and use mirror, device selection, or capture controls as needed.
- Read the reported resolution, aspect ratio and observed frame rate below the preview.
- If you take a snapshot, review it and download it — it never leaves your device.
- Press Stop to end the camera stream; the active indicator will turn off.
What it detects
- Whether your browser can open the camera and receive frames
- The negotiated resolution, aspect ratio and facing mode
- A browser-observed estimate of delivered frame rate
- Whether the image looks correct to you (focus, exposure, color) as a visual check
What it can’t detect
- A sensor’s certified specifications or true optical quality
- Hardware defects versus driver, privacy-shutter or lighting problems
- Anything about the people or scene — we never run face detection or AI analysis
Troubleshooting
| Symptom | What to do |
|---|---|
| Permission denied | Click the padlock in the address bar, allow the camera, and reload the page. |
| Black image | Check for a physical privacy shutter, and make sure no other app is using the camera. |
| Device busy | Close other apps (video calls) that hold the camera, then retry. |
| Wrong camera | Use the camera selector to switch between front and rear or external devices. |
| Low resolution or frame rate | Improve lighting, close heavy background apps, and try a wired or less-busy connection. |
FAQ
Is my video uploaded?
No. The preview and any snapshot stay on your device and are never sent to a server.
Why is my camera light on?
Your camera is active while the test runs. It turns off when you press Stop or navigate away.
Why does it need HTTPS?
Browsers only allow camera access on secure (HTTPS) origins for your safety.
Do you run face detection?
No. We never perform face detection, recognition, or any AI analysis of your video.
Can I use my phone’s camera?
Yes, and you can usually switch between front and rear cameras with the selector.
Why is the frame rate lower than my camera’s spec?
The value is what the browser actually delivered, which is affected by lighting, USB bandwidth and system load — not a sensor rating.
Related tests
Preview your camera, pick a device, mirror or rotate, and read the real track settings — resolution, aspect ratio and observed frame rate.
Adjust zoom, torch and focus where your camera exposes them, applied safely with applyConstraints. No dead controls.
Estimate your camera’s delivered frame rate with requestVideoFrameCallback, showing average, minimum and the reported rate.