Type a short message, broadcast it as a burst of musical tones through your speaker, and decode it back to text on another device (or tab) listening with its microphone. No accounts, no server — everything happens live in the browser.
Encodes your text into a sequence of tones (a short pentatonic melody, not a harsh chirp) and plays it through your speaker.
Your text is converted to bytes, wrapped with a length header and Reed-Solomon parity (so a few masked tones can still be recovered), then split into 4-bit chunks. Each chunk becomes one of 16 tones, evenly spaced and confined to less than one octave — this trades some musicality for a guarantee that no tone's natural harmonic distortion can be mistaken for a different tone. A single high marker tone signals "start"; "end" is a dual-tone chord (low in-band + high above the data band) so a lone tone in the room can't fake it. If your message starts with a known shortened-URL prefix (like is.gd), that prefix is replaced with a single flag byte instead of being transmitted character-by-character. Repeats are merged by majority vote, so one punched-through pass can still yield a clean decode.
Uses your microphone to listen for the tone sequence and decodes it back into text, locally, on this device.