Device Tests
8 free toolsTest your keyboard, mouse, webcam, microphone, screen, touchscreen, and gamepad.
Device tests check the hardware in front of you using the browser's own APIs: every key and its rollover limit, dead or stuck pixels, microphone and webcam permissions, touchscreen dead zones and ghost touches, controller stick drift and rumble. Each test explains what a failure usually means, and whether it is the device, the cable, or a browser permission.
Tests use browser device APIs on your machine; camera and microphone streams are shown locally and never recorded or sent anywhere.
All 8 tools
Mic Test
Test your microphone with a live level meter, waveform, and playback
Voice Recorder
Record audio from your microphone in the browser with pause, resume and a live waveform. Download as WAV or the native format. Nothing is uploaded.
Webcam Test
Test your camera with a live preview, real resolution, and measured FPS
Screen Test
Find dead pixels and check uniformity with fullscreen test patterns
Keyboard Test
Test every key with a visual board, event log, and rollover counter
Gamepad Tester
Test controller buttons, sticks, triggers, and vibration
Touchscreen Test
Find dead zones and unresponsive spots on your touchscreen
Mouse Test
Test mouse buttons, scroll wheel, double-click chatter, click speed, and polling rate
Guides
From the blog: the mechanisms, standards, and edge cases behind these tools.
- Stick Drift, Dead Zones and Ghost Touches: Testing Input in a Browser Why worn analog sticks drift, how radial dead zones hide it, what the Gamepad API reports, and how to catch touchscreen dead zones and ghost touches. Sep 29, 2026 · uses Mic Test, Screen Test, Keyboard Test +3
- Keyboard Ghosting and N-Key Rollover, Explained Why cheap keyboards drop keys when you hold three at once, what NKRO actually requires over USB, and why a browser-based keyboard test can never see quite everything. Jul 29, 2026 · uses Mic Test, Webcam Test, Screen Test +3
- Dead Pixels vs. Stuck Pixels: How to Tell, and What Your Warranty Actually Covers A dead pixel and a stuck pixel look similar and are completely different failures. How to distinguish them in 30 seconds, what the ISO pixel-fault classes allow, and whether "pixel fixer" videos do anything. Jul 29, 2026 · uses Mic Test, Webcam Test, Screen Test +2
- Mouse Double-Clicking by Itself? Switch Chatter vs. Software A mouse that double-clicks on its own is usually a bouncing switch, not a setting. How chatter works, how to prove it in a minute, and what a browser can measure. Oct 14, 2026 · uses Keyboard Test, Gamepad Tester, Touchscreen Test +1
- Record Voice Memos on Your Laptop Without Installing Anything (and Why Safari Can Give You an M4A) Record audio straight from a browser tab, no app and no upload. What each browser saves (WebM, M4A, WAV), how big the files get, and how to fix a silent recording. Oct 16, 2026 · uses Mic Test, Voice Recorder, Webcam Test
- Why Your Browser Can't Access Your Microphone (And Why the Usual Advice Doesn't Help) Every getUserMedia error name, what actually causes it, and the failure mode nobody writes about: a response header that kills the permission prompt before it ever appears. Jul 29, 2026 · uses Mic Test, Voice Recorder, Webcam Test
- Webcam Goes Black or Freezes Mid-Call? Here's What's Actually Happening Your camera worked, then went black, froze, or turned choppy. How browsers signal device loss, why a black picture is often by design, and a fix order. Oct 6, 2026 · uses Mic Test, Webcam Test
- A CSS px Is Not a Device Pixel: PPI, devicePixelRatio, and rem The CSS px is a viewing-angle unit, not a dot on your panel. How PPI, devicePixelRatio and min-resolution connect them, and why rem sits on top of all three. Sep 29, 2026 · uses Screen Test
- Why Browser Text-to-Speech Sounds Different on Every Machine speechSynthesis is a thin wrapper over voices you did not install and cannot ship. The first getVoices() call legitimately returns an empty list, Chrome has required a user gesture since M71, long text dies around 15 seconds, and half the voices send your text to a server. What the spec guarantees, and what it does not. Aug 31, 2026 · uses Mic Test