Each test runs on this device. The camera and microphone switch on only when you press Start and switch off when you press Stop or change tabs.
Testing a microphone
Press Start microphone and allow access. The bar shows the level as you speak: normal speech at arm’s length usually sits between −40 and −15 dB, and a level that touches 0 dB will distort. If several microphones are connected, pick one from the list. Record 5 seconds to hear how you sound; the clip is played back from memory in this tab and never leaves it.
Testing a webcam
Press Start webcam to see the live picture. The resolution is the size the camera is actually delivering, which can be lower than its box says if the light is poor or another app limits it. Ask for 1080p or 4K to see the most it can do. The frame rate is counted from the frames your browser receives. Snapshots match the preview, so they are flipped while Mirror is on.
Finding dead or double-typing keys
Click the test area and press every key. A key that never turns green may be dead, or it may be one your system keeps for itself, such as Fn, the Windows key or Print Screen on some laptops. A key pressed twice within about 30 ms is reported as chatter, a common sign of a worn switch. Holding a key shows repeats, which is normal; a key that repeats without being held is stuck.
Checking a screen for dead pixels
Clean the screen first, then start the colour test and look closely at each colour. A dead pixel stays black on white, a stuck pixel stays one colour on black, and backlight bleed shows as bright patches near the edges on black. The refresh rate is an estimate from your browser’s drawing speed; power saving or a busy computer can make it read lower.
Privacy and permissions
Your browser asks before this page can use the camera or microphone, and you can withdraw access at any time from the address bar. Nothing is recorded unless you press Record or take a snapshot, and those stay on your device until you choose to save them.