Privacy Policy

Last updated: 21 October 2026

Summary

In ChatGPT, Music Block receives the music ChatGPT writes for your request and anonymized identifiers from ChatGPT. It never receives your conversation, your name or your email address. No account is needed.
On the website and in the editor, you sign in with Google or an email link. We store your account details, your library and your editor projects, including your chat with the editor's AI assistant.
To run the editor we send your requests and scores to Anthropic (AI) and scanned sheet music to Flat (music recognition). Payments go through Stripe.
We don't sell your data, show ads, or train AI models on your content.
Deleting your account from the account page erases your account, library and projects.

Who we are

Music Block ("we", "us") runs the Music Block app in ChatGPT and the website at musicblock.app, including the notation editor, and is responsible for the data described here. Contact us at support@musicblock.app.

When you use Music Block in ChatGPT

When ChatGPT uses Music Block, our server receives the music the model wrote (notes, frets, durations, chord symbols, titles and labels), checks it and turns it into notation. ChatGPT also sends an anonymized identifier for your ChatGPT account that is specific to this app, an identifier for the conversation, and a browser or device description. We use these to limit how often the app can be used, to count usage, to connect the Save button to your library if you create an account, and to tell whether you've used the app before. We don't receive your ChatGPT account details or the text of your conversation, though the titles and labels ChatGPT writes for a piece may reflect what you asked for.

We store each piece of music sent to us, including ones that fail our checks, together with those identifiers. Renders are private when created. A render gets a public link, which anyone who has the link can open, only when you press Share or open an export from it.

When you use the website and editor

Account. With Google sign-in we store your name, email address and profile picture URL; with an email link, only your email address. We also store sign-in sessions and, if you linked one, your anonymized ChatGPT identifier.
Library. Examples you save from ChatGPT.
Editor projects. Your scores and their version history, hand edits, your messages to the AI assistant and its replies, the changes it proposed, comments on bars, and the browser description from when the project was created.
Imports. MusicXML and Guitar Pro files you open become projects. For scanned sheet music (PDFs and photos) we keep what was read from the scan and a preview image of it, not the original upload.
Feedback and surveys. Messages and screenshots you send with "Send feedback", with your browser details and, if you choose to include it, a copy of the project and recent chat. Your answers if you take our user survey.
Billing. Your plan, credit balance, a record of what used credits, automatic top-up settings, your Stripe customer ID and the country you paid from. Stripe handles your payment details; we never see your full card number. To allow one free trial per person, we keep a one-way hash of your email address.

How we use it

to provide Music Block: render, play, save, edit, import and export music, and run share links;
to charge for credits, apply plans, and prevent abuse of free trials and usage limits;
to send emails you need: sign-in links and billing notices (for example, when credits run low or a payment fails), and occasional messages about the service such as a survey invitation;
to fix problems and improve Music Block: we review stored renders, projects, AI turns and feedback to find bugs, improve how music is checked and engraved, and answer support requests;
to keep the service secure and to meet legal, tax and accounting obligations.

If you are in the European Economic Area or the UK: we process your data to perform our contract with you (the service you asked for), for our legitimate interests in running, securing and improving Music Block, to meet legal obligations, and with your consent where we ask for it (for example, when you include project context in feedback).

AI processing

When you ask the editor's assistant for something, we send your message, the conversation so far in that project and the relevant parts of your score to Anthropic, whose Claude models write the reply and the music. We also use Anthropic to suggest first messages for a new project. Under Anthropic's commercial terms, data sent through its API is not used to train its models. We don't train AI models on your content either. In the ChatGPT app, the music is written by OpenAI's models as part of your ChatGPT conversation, which is covered by OpenAI's privacy policy, not this one.

Services that process data for us

Vercel: hosting, and short-lived server logs (such as request times and status codes).
Neon: the database where everything above is stored.
Anthropic: the AI models in the editor.
Flat (Tutteo): reading scanned sheet music, and making MP3 exports (the score is uploaded for the export and deleted right after).
Stripe: payments, subscriptions, invoices and tax records.
Google: sign-in, if you choose it.
Resend: delivering our emails.
PostHog: usage analytics and error reports.

These providers process data on our behalf, only as needed to provide their service. Several are in the United States, so your data may be processed outside your country; where the law requires it, transfers are covered by the providers' data protection terms, such as the EU Standard Contractual Clauses. We may also disclose data if the law requires it, to protect the rights and safety of our users or of Music Block, or as part of a sale or reorganization of the service, in which case this policy continues to apply. We don't sell personal data.

Cookies and analytics

We use a cookie to keep you signed in. PostHog analytics, which go through our own domain, use a cookie and local storage to recognize returning browsers, and record which pages and features are used and errors that happen. Analytics events are tied to random or anonymized IDs, never to your name or email address. Fonts and sounds are served from our own domain. We don't use advertising or cross-site tracking cookies.

How long we keep data

Account data, library items and editor projects are kept until you delete them or your account. Renders from the ChatGPT app are kept to serve share links and improve the service; they are tied only to anonymized ChatGPT identifiers. Records of payments are kept by Stripe as long as tax and accounting law requires. Deleted data may remain in database backups for a short time before they expire.

Deleting your data

You can delete editor projects at any time, and they are erased right away. Removing an item from your library hides it, so you can undo; it is erased with your account. Deleting your account from the account page erases your profile, sign-in sessions, the link to your ChatGPT identifier, your library, all your editor projects (with their history and chat), your scan imports, your feedback, and your credits and billing records in our database. It also ends any subscription and turns off automatic top-up.

What remains after deletion:

renders from the ChatGPT app, which hold only music and anonymized identifiers; share links keep working;
survey answers, no longer linked to your account;
your Stripe customer record and invoices, kept for tax records;
the one-way hash of your email address, so a new account with the same email doesn't get a second trial.

To have renders tied to your ChatGPT identifier deleted, or for any other request, email us.

Your rights

Depending on where you live, you may have the right to access, correct, export or delete your personal data, to object to or restrict how we use it, and to withdraw consent. The editor exports your scores (MusicXML, PDF and other formats) at any time. For anything else, email support@musicblock.app from the address on your account and we will reply within 30 days. You can also complain to your local data protection authority.

Children

Music Block is not meant for children under 13, and we don't knowingly collect their personal data. If you believe a child under 13 has created an account, email us and we will delete it.

Security

Data is encrypted in transit, access to stored data is limited to the people who run Music Block, and payment details stay with Stripe. No system is perfectly secure, but we will tell affected users about a breach that puts their data at risk, as the law requires.

Changes to this policy

We will post any changes here with a new date, and email account holders about significant changes.

Contact

Questions or requests? Email support@musicblock.app or see the support page.