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

narrayana swamy — Sat, 28 Mar 2026 16:23:25 +0000

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 smoothly.

The stereo panning for left/right channel isolation uses createStereoPanner() — simple but effective.

Try it
https://miccheckonline.com — free, no signup, works on Chrome, Firefox, Edge, Safari.

Would love feedback from the dev community — what tools are missing? What should I build next?

Forem: narrayana swamy

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