LazyTools

🔒 Every tool runs in your browser — the files and values you enter are never uploaded to any server. How it works

Music & Audio Tools

For musicians and producers — convert notes to frequencies, turn tempo into delay times, tap out a BPM, practise to a precise metronome, work out intervals, transpose chords and size up audio files. Exact music maths, running entirely in your browser.

Frequently asked questions

Are these music tools accurate?

Yes — they use exact, standard formulas: equal-temperament pitch (A4 = 440 Hz, the ISO 16 standard), BPM-to-milliseconds timing, intervals in cents, and PCM audio file size. The metronome uses sample-accurate Web Audio timing.

Do I need to install anything?

No — everything runs in your browser. The metronome and tap tempo use built-in Web Audio and timing, with no plugins or sign-up.

Can I change the tuning reference?

Yes — the note frequency calculator lets you set A4 to 440, 432, 442 or any reference, and retunes every note accordingly.

Is my data uploaded?

No. Every tool runs entirely in your browser — nothing is sent to a server, and they work offline.