# Tonegrid

> Light up squares to build looping melodies and beats, then arrange them into songs. Tonegrid is a tone matrix for your browser: switch squares on and a playhead turns them into a looping melody, with a separate drum grid for the beat. Pick a key and scale so every note fits, shape the groove with tempo and swing, chain up to eight patterns into a song, and export WAV, MIDI, MP3 or a share link. Every sound is synthesized on your device and nothing plays until you press Play.

Tonegrid (Tone matrix & beat sequencer) is a premium app of usefulweb.app (https://usefulweb.app/): a full program that runs in the browser. Its engine is deterministic and the same functions are exposed as tools, so an agent can compute exactly what the app shows.

## Use it
- Landing page: https://tonegrid.usefulweb.app/
- Workspace (browser app): https://tonegrid.usefulweb.app/app - open a project with https://tonegrid.usefulweb.app/app#project=<base64url-encoded project JSON> or a template with https://tonegrid.usefulweb.app/app#template=<id>
- Project file format (JSON Schema): https://tonegrid.usefulweb.app/project.schema.json
- Tutorials: https://tonegrid.usefulweb.app/tutorials
- JSON API: POST https://tonegrid.usefulweb.app/api/v1/tools/<toolId>/calculate (catalog: https://tonegrid.usefulweb.app/api/v1/tools)
- OpenAPI: https://tonegrid.usefulweb.app/openapi.json
- MCP (Streamable HTTP): https://tonegrid.usefulweb.app/mcp

## Engine tools
- [Tonegrid Pattern Builder](https://tonegridpatternbuilder.usefulweb.app/): Turn x-and-dot step notation into a Tonegrid project and a MIDI file. API: POST https://tonegrid.usefulweb.app/api/v1/tools/tonegrid-pattern-builder/calculate · MCP tool `tonegrid_pattern_builder`
- [Tonegrid Scale and Sequence Planner](https://tonegridscaleplanner.usefulweb.app/): Map a scale to a note grid and plan your melody. API: POST https://tonegrid.usefulweb.app/api/v1/tools/tonegrid-scale-planner/calculate · MCP tool `tonegrid_scale_planner`
- [Universal Audio Converter](https://audioconverter.usefulweb.app/): Convert MP3, WAV, FLAC, Ogg, Opus, M4A and AIFF with bitrate and sample-rate control. API: POST https://tonegrid.usefulweb.app/api/v1/tools/audio-converter/calculate · MCP tool `audio_converter`
- [Audio Cutter & Merger](https://audiocuttermerger.usefulweb.app/): Trim audio, keep or remove ranges, fade in/out, or join up to 10 clips with crossfades. API: POST https://tonegrid.usefulweb.app/api/v1/tools/audio-cutter-merger/calculate · MCP tool `audio_cutter_merger`
- [Audio Loudness Normalizer](https://audioloudnessnormalizer.usefulweb.app/): Measure LUFS and true peak, then normalise to Spotify, podcast or EBU R 128 targets. API: POST https://tonegrid.usefulweb.app/api/v1/tools/audio-loudness-normalizer/calculate · MCP tool `audio_loudness_normalizer`

## Formats
- Import: Tonegrid project (.tonegrid.json, versions 1–3), Share link (#project=), Text pattern (x-and-dot notation)
- Export: Tonegrid project (.tonegrid.json), WAV audio (pattern loop or song), MIDI file (.mid, General MIDI), MP3, Ogg Vorbis, Opus, M4A, FLAC (via site tools), Share link, Text pattern

## Limits
- Steps are sixteenth notes of equal length (plus swing); there are no note lengths, velocities per square, triplets or tempo changes within a song.
- All patterns in a project share the same grid sizes, key, scale and sound.
- Sounds are simple built-in synthesizers; you cannot load your own samples or plug-ins.
- WAV and other audio exports are limited to five minutes and 8,000 notes and drum hits; converting to compressed formats needs an internet connection.
- Playback timing depends on your browser and may pause or stutter while the tab is in the background or the device is busy.
- MIDI export contains notes only, not the Tonegrid sounds or mixer settings.
- There is no audio or MIDI recording from instruments and no live collaboration.