Last updated: November 2026. midicat.org is run by Chai Webs (chaiwebs.co.uk).

When you drop a song on the page, the whole conversion happens inside your own browser, on your own computer. The song, the separated instruments, the MIDI file and everything you hear on the page exist only in that browser tab.

• Your audio is not uploaded to midicat.org or to anyone else.
• We keep no copy of your audio, your MIDI or your stems. We could not look at them if we wanted to.
• Close or reload the tab and all of it is gone, unless you chose to save the MIDI or the stems to your own computer.

To save you downloading things twice, your browser stores a few items for midicat.org on your own device:

• the instrument-separating model (a large file, up to about 285 MB), so later visits start straight away;
• the sound sets you have listened to, in the browser's ordinary cache;
• a few small settings: the sound set you last chose, and a short note of how far the last conversion got (used to explain what happened if the browser ran out of memory). That note can include the file name of the song. It stays on your device.

None of this is sent to us. You can remove all of it at any time by clearing the site data for midicat.org in your browser's settings.

Some of the files midicat needs are fetched from other companies' servers. They receive what any website receives when you load a file from it - your IP address and basic details of your browser - but nothing about your music.

• jsDelivr serves the software that runs the models. jsDelivr's privacy policy
• Hugging Face serves the instrument-separating model. Hugging Face's privacy policy
• Our web hosting company keeps the usual server logs of which pages were requested, for security and to keep the site running.

We use Google Analytics to see how many people visit midicat.org, which pages they look at, roughly where in the world they are and what kind of device and browser they use. It helps us find out what to improve.

• Google Analytics uses cookies and similar identifiers to tell one visit from another. It records things like the pages you open, how long you stay, the site you came from, your approximate location (worked out from your IP address) and your browser and screen size.
• It knows nothing about your music: not the file, not its name, not what was converted. None of that leaves your computer.
• We see the results only as totals and charts. We cannot tell who you are.
• You can stop Google Analytics on every website with Google's opt-out browser add-on, or by blocking cookies in your browser.

midicat.org is free to use and is paid for by advertising from Google AdSense. The adverts sit in the spaces around the midicat panel, never inside it.

• Third-party vendors, including Google, use cookies to serve adverts based on your earlier visits to this website or to other websites.
• Google's use of advertising cookies enables it and its partners to serve adverts to you based on your visits to this site and to other sites on the internet.
• Google and its partners may also use web beacons, your IP address and other identifiers to deliver adverts, limit how often you see one, measure how they perform and prevent fraud.
• Other advertising companies that work with Google may serve adverts here in the same way.

Your choices:

• You can turn off personalised advertising from Google at adssettings.google.com.
• You can opt out of many other companies' use of cookies for personalised advertising at aboutads.info (or, in the UK and Europe, youronlinechoices.com).
• Where the law requires it, including in the UK and the European Union, you are asked for your consent before advertising cookies are used, and you can change your mind at any time.
• You can also block or delete cookies in your browser's settings. midicat itself works the same either way.

How Google uses information from sites that use its services (both Analytics and advertising) is explained at policies.google.com/technologies/partner-sites. The adverts are chosen by Google, not by us, and we never see who you are.

• We do not ask for your name, email address or any account.
• We do not use your music, or anything made from it, for any purpose. We never receive it.
• We do not sell information about you.

Under UK and EU data protection law you have the right to ask what personal information an organisation holds about you, and to have it corrected or deleted. midicat.org itself keeps no record of who you are - the visitor statistics are held by Google - but if you have any question about this page, please get in touch through chaiwebs.co.uk. If you are in the UK and are unhappy with how your information has been handled, you can also contact the Information Commissioner's Office at ico.org.uk.

If this policy changes, the new version will be posted on this page with a new date.