I built a free browser-based hardware testing toolkit — here's why

The problem I kept running into Every time I joined a video call, I'd wonder — is my mic actually working? Is my webcam on? Are my speakers outputting to both channels? Every tool I found either required a download, had annoying ads, or only tested one thing at a time. So I built MicCheck Online — a free collection of hardware testing tools that run entirely in your browser. What it includes Mic Test — real-time audio levels, clipping detection, device switching Webcam Test — camera preview, resolution & FPS readout Speaker Test — left/right channel isolation, frequency presets (60Hz–16kHz), full sweep Headphone Test — L/R channel isolation Screen Tests — dead pixel checker, white/black/color screens, backlight bleed, uniformity Keyboard Test — every key visualized in real time Mouse Test — button, scroll, and movement tracking The tricky parts: The speaker frequency sweep was interesting to build — using OscillatorNode and exponentialRampToValueAtTime to sweep from 20Hz to 20kHz s