Extensions inspire

Flat - Music scores and guitar tabs editor



Tutteo Limited - Flat

Music & Radio




February 07, 2019

Webstore Link:

Developer's site:


version 8.1.0  - Download ZIP file

version 7.0.0  - Download ZIP file

version 6.0.2  - Download ZIP file

version 5.1.1  - Download ZIP file

version 5.1.0  - Download ZIP file

version 5.0.0  - Download ZIP file

version 4.2.9  - Download ZIP file

version 8.0.0  - Download ZIP file


Create and edit your music score documents with your Chrome browser in realtime with your friends or colleagues.

Flat brings the following features among many others:

✓ Your music notation editor online in your web browser
✓ Real-time collaboration and offline edition if you lose your internet connection
✓ Compose with your MIDI devices: plug your device and play!
✓ MusicXML, MIDI, PDF and Audio (MP3 and WAV) compatibility
✓ Read and write music notation and guitar tablatures, together
✓ Smart History: Browse all the modifications you made, note after note
✓ Collaborate with video within Google Hangouts
✓ Percussion instruments and notation to create amazing drum scores
✓ Online digital and visual metronome to help you to practice easily
✓ Easy way to add chords with an useful completion

Discover our new v8 version: https://blog.flat.io/flat-v8-is-now-live/

With love ♥
The Flat.io Team

► Some detailed features: "inside Flat, the online music score editor":

✓ Online in your web browser

Flat is an online web music score editor, everything you need to use our service is a recent web browser. You can use desktop, laptop, tablet and even your mobile phone to browse and edit your sheet musics and guitar tabs.

✓ Collaborative music scores

Create and modify your sheet music with your friends and colleagues at the same time.

You want to make an adaptation of your favorite music with your music band or edit a document with all your school class? Just share your score and open it at the same time.

You work remotely and need a video chat? You can open your music documents in a Google Hangout.

✓ Compose with your MIDI devices

Play on your controller, we transcribe in live the notes and their duration. Just plug your MIDI device to get started, nothing to install.

✓ MusicXML, MIDI, PDF and Audio compatible

Flat supports MusicXML, a file standard used by nearly 200 music notation softwares.
You already wrote some music scores in another music notation software? Just import them in our service in few clicks.
We believe in cloud reversibility: you can easily export all your documents created and edited on Flat into MusicXML files, and open them in another software easily.

For performance time, you can export your scores in PDF format suitable for print.

Finally, you can listen to your songs whenever you want with the MP3 & WAV export.

✓ Sheet music Smart History

Note after note, every modification you make is save in Flat. Use our Smart History to browse them and restore your work at a specific change. This feature is great to discover the creation process of a music score, or simply discover the work your collaborators made when you were off.

✓ Use Flat within Google Hangouts, the best of the real time edition of Flat and the Google Hangouts video calls at the same time

Turn any edited music score on Flat to a Hangout with live video call by simply clicking in the Google Hangouts icon in the editor. Your current sheet music will directly be opened in a new video Google Hangouts, you just need to invite new friends or colleague to join it.

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What has inspired us?

Extore is a team of professionals who are passionate about creating extensions for web browsers. This devotion also gives us opportunity to appreciate work of other people. We get inspired by useful, open source extensions made by developers all over the world. Our strong belief is that one should share helpful add-ons with others. That’s why we’d like to present you our ever-growing list of favourite extensions that have inspired us. Moreover, as you probably have already learned, sometimes struggling for the best brings an end to the good. Talking about add-ons it often turns out that an upgrade is worse then previous version. Also it can become really tricky to get back to the beloved version of your favourite extension. That’s why we’re going to make not only the latest, but all versions of our favourite (and we hope yours too) add-ons available for download. No more compromises, just stick to the version you really like!