Privacy

1. Who we are

Instrufilt is an open-source project that anyone can contribute to. The hosted service (your account) is operated by Betania.io, a business registered in Serbia, which is the controller of the personal data described below (“we”, “us”). Contact: hello@betania.io.

2. One account across the family

Instrufilt and its sibling Karafilt are operated by the same company on one shared account system. Concretely:

• Identity is shared. Your email address, sign-in method, and optional display name are one record used by both products — sign up for either and you can sign in to both.
• Email preferences are shared. There is one announcement list for the family: opting out of announcement emails opts you out for both products at once.
• Product usage data is stored per product.What you practise with Instrufilt (sessions, votes, badges) is stored in Instrufilt's own tables and shown only in Instrufilt; Karafilt's data likewise stays with Karafilt.
• Deletion covers both.Deleting your account deletes it for both products, along with each product's data tied to it.

3. The browser extension

This section is the privacy disclosure for the Instrufilt browser extension (Chrome Web Store listing included).

• Isolation is 100% local.Every isolation mode processes the tab's audio inside your browser (WebAssembly). The audio never leaves your machine and we have no way to see it.
• Sign-in is required.The extension asks you to sign in with your account (shared with Karafilt, see section 2) before use. It uses your site session (never your password) to confirm you're signed in; this is how we keep track of our users.
• Lyrics lookups.To find the lyrics under the chord chart, the extension sends the page's media title (e.g. a YouTube video title, artist/track) and the track duration to karalyr.com (our sister project) and lrclib.net. These requests are not linked to any account and contain no personal data; the services see them like any web request (including your IP address) under their own privacy policies.
• Online chord charts. When the Online chordstoggle is on and the song is a YouTube video, the extension may send the video's address — nothing else — to karalyr.com and to Songle (widget.songle.jp, a research service operated by AIST in Japan) to fetch a ready-made chord chart. Turn the toggle off and no chord request leaves your machine; chords are then detected on your device from the audio itself.
• Settings stay local.Your preferences (isolation mode, isolation amount, output level, chord toggles) are stored in your browser's extension storage. The isolation mode in use is also included in the usage reports described next.
• Usage reporting to Instrufilt.While you're signed in and the isolation is active, the extension reports each practice session to our own servers: the page's address and title, the song and artist when detected, the isolation mode, how long it ran, timestamps, and the extension version. This data is tied to your account — you can see it as the practice stats on your account page — and we use it to understand how the isolation is used and to improve it. It is deleted when you delete your account.
• Song ratings. If you choose to rate whether the isolation worked on a song (a like/dislike vote, optional comment), that vote is stored with your account together with the song and page details above. Aggregated, anonymous per-song counts may be shown publicly; your email and comment are not.
• Achievements.The badges on your account page are derived from the practice data described above (hours practised). Top achievers appear on the home-page Hall of Fame and the practice leaderboards: with your display name if you set one, otherwise as an anonymous entry showing only the badge stats, with nothing linking it to your account. Unlocking a badge may trigger a notification email unless you've opted out of announcement emails.
• Public aggregate totals. The home page shows all-time community totals (practice time, songs, badges earned). These are sums across all users and contain no per-user data.
• No third-party analytics or trackers. The extension contains no advertising, third-party analytics, or cross-site tracking code. The usage data described above goes only to Instrufilt, nowhere else.

4. Data we collect

The audio you practise over is never collected — every isolation mode runs entirely in your browser and nothing is uploaded.

5. Lawful basis (GDPR)

• Performance of contract, your email address. Required to provide and identify the account you signed up for.
• Legitimate interest, practice activity and song votes (like/dislike plus any comment), limited to showing you your own stats and improving the vocal isolation. You can object at any time by emailing us, and deleting your account removes this data entirely.
• Legitimate interest, occasional product announcement emails about the family's products (one shared list). Every such email carries a one-click unsubscribe link, and you can also opt out from your account page — opting out stops them immediately and permanently, for the whole family.
• Legitimate interest, IP address and technical logs, limited to security, abuse prevention, and capacity planning.

6. Who we share data with (subprocessors)

• Supabase, authentication and database (your account).
• Vercel, website hosting.

Lyrics and chord lookups from the extension (section 3) go directly from your browser to lrclib.net and Songle (widget.songle.jp) — independent services, not our subprocessors — and to karalyr.com, our own sister project. We do not share data with advertisers, brokers, or other third parties.

7. International transfers

Some subprocessors above operate outside the EU/EEA (notably Supabase and Vercel, in the United States). Where required, transfers are governed by the European Commission's Standard Contractual Clauses (SCCs). You can request a copy of the relevant clauses by emailing the address in section 1.

8. Your rights

Under GDPR (EU/UK) and the CCPA (California), you have the right to:

• Access the data we hold about you
• Correct inaccurate data
• Delete your data (right to be forgotten), you can delete your account yourself from the account page at any time — deletion covers both family products (section 2)
• Export your data (data portability)
• Restrict or object to processing
• Opt out of any future sale of personal information (we do not sell)
• Lodge a complaint with your local data protection authority

To exercise any of these, email hello@betania.io. We respond within 30 days.

9. Cookies & analytics

We use only essential cookies, the session cookie that keeps you signed in. The browser extension uses this same session (never your password) to show your signed-in status in its panel.

For aggregate page statistics this website uses Vercel Web Analytics, and to measure page performance we use Vercel Speed Insights. Both are cookieless: they set no cookies, store no identifiers on your device, and do not track you across sites, we only see anonymous, aggregated counts and performance timings. We do not use advertising, cross-site tracking, or cookie-based analytics (such as Google Analytics). If that ever changes, we'll show a consent banner first.

10. Children

Instrufilt is not directed at children under 16. We do not knowingly collect data from anyone under that age. If you believe a child has provided us data, email us and we'll delete it.

11. Security

Data is encrypted in transit (TLS) and at rest. No system is perfectly secure; if we ever experience a breach affecting your data, we'll notify you within 72 hours.

12. Changes

Material changes will be announced by email at least 30 days before they take effect. The last-updated date at the top of this page reflects the most recent revision.