Measurement Tools

Free, private measurement tools that run entirely in your browser — no upload, no account. Pick a tool below; more land here as they ship.

Guitar Tuner

Tune a guitar by ear with your microphone — many tunings

How Guitar Tuner works?

Keyboard Tester

Test keys for dead keys, ghosting & rollover

How Keyboard Tester works?

Pure Red Screen

Red screen test for dead pixels & OLED burn-in

How Pure Red Screen works?

Country Size Compare

Drag country outlines to compare their true size on a map

How Country Size Compare works?

Every tool runs in your browser — no upload, no account, free.