Privacy Policy
Last updated 21 September 2026
Crimson Reader is a reading application. It is built local-first, which means the plainest thing in this policy is also the most important one: the books you open stay on your own computer.
Your book files are never uploaded. When you open an EPUB, PDF or Word file, it is read and stored by your browser, on your device. It is not sent to us, and we have no copy of it and no way to obtain one.
Two deliberate exceptions, described in full below: passages you highlight, and text you play as narration.
You can use it without giving us anything
Signing in is optional. Without an account you can open books, read, annotate and listen, and nothing is stored anywhere but your own browser. There is no account to create before you can read.
What we store if you do sign in
An account exists to carry your reading across devices. It holds the following, and nothing else:
| What | Why |
|---|---|
| Your email address and, if you sign in with Google or GitHub, the name and avatar they give us | To identify your account and send sign-in links |
| Which books you have — file name, title, author, how far through you are | So your place is the same on your phone as on your laptop. Not the book itself. |
| Highlights and notes — including the passage you highlighted and anything you wrote about it | So annotations follow you between devices. This is book text, and it is the exception to the rule above. |
| Bookmarks | Same reason |
| Reading streaks, time read, experience and rank including when each reading session started, by your device’s clock, and how long it lasted | The retention features, and the leaderboard if you join it. The app’s administrators can see these figures per account, to understand how the app is used. |
| Your leaderboard profile, if you join the leaderboard — your chosen name, rank, experience, streaks, badges and how many books you have finished, plus their titles and authors if you turn that on | Public by design — anyone can open your profile from the leaderboard. Book titles stay off it unless you share them, and leaving the leaderboard removes the profile. |
| Ratings and reviews you post | These are public by design — other readers see them next to your display name |
| A push subscription, if you turn on reading reminders | To send the reminder. Delete it by turning reminders off. |
Narration sends text to a speech service
When you play narration, the passage being read aloud is sent to a text-to-speech provider so it can be turned into audio. Only the passage currently being narrated is sent — never the whole book, and never anything identifying you. The audio comes back, is cached in your browser, and we do not keep it.
If you would rather no text left your device at all, your browser has a built-in voice that runs entirely locally. It is what signed-out readers get, and it never contacts a server.
What we do not do
- No analytics. There is no Google Analytics, no product analytics, no session recording. We genuinely do not know how many people use this.
- No tracking cookies and no advertising. We set exactly one kind of cookie — the one that keeps you signed in. There are no third-party cookies, no pixels and no ad networks.
- No selling or sharing of personal data, in the sense those words carry under GDPR and the CCPA. There is no one to sell it to; this is not the business model.
- No profiling and no automated decisions about you.
Cookies
One cookie, holding your sign-in session, and only after you sign in. It is marked Secure so it never travels over an unencrypted connection, and SameSite=Lax so it is not sent from other sites. It is strictly necessary to keep you signed in, which is why there is no cookie banner: there is nothing optional to consent to. Sign out and it is gone.
Who else touches your data
These are the only third parties involved, and each does one job:
| Service | What it does |
|---|---|
| Supabase | Stores the account and sync data listed above, and handles sign-in |
| Vercel | Hosts and serves the site. Like any web host, its servers see the IP address of requests |
| RunPod | Turns the passage you are listening to into speech |
| ElevenLabs | An alternative narration voice, available only to administrators |
| Resend | Delivers the email, and only when you write to us through the contact form or a bug report |
| Project Gutenberg | Supplies public-domain books when you download one. The download is proxied through our server, so Gutenberg does not see you |
| Google Fonts | Serves the typefaces the site is set in. Loading a font from Google reveals your IP address to Google — this is the one third party that sees you without any action on your part, and we intend to self-host these so that it does not |
IP addresses
Our servers use the IP address of a request to enforce rate limits — the mechanism that stops one source from flooding the narration or contact endpoints. It is held in memory for the length of a rate-limit window and written to no database. Our host keeps its own server logs, as every web host does.
How long it is kept
For as long as your account exists. Delete your account and every row listed above is deleted with it — the database enforces this, so nothing is left behind for us to forget about. Reviews you posted publicly may remain visible, with your authorship removed. Anything stored only in your browser is gone the moment you clear its data.
Your rights
You can ask for a copy of what we hold about you, ask for it to be corrected, or ask for it to be deleted. Because so little is collected, these requests are usually easy to answer. If you are in the UK, EU or EEA, these rights come from the GDPR; if you are in California, from the CCPA; and this policy is written to be honest to both.
Children
Crimson Reader is not directed at children under 13, and we do not knowingly collect their data. If you believe a child has created an account, write to us and it will be removed.
Changes
If this policy changes, the date at the top changes with it. Material changes will be announced in the application rather than made quietly.
Contact
Use the contact form on the home page for any question about this policy, or to make any of the requests above.
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