Privacy Policy — MangaLens

Last updated: August 2026

MangaLens is a browser extension that translates manga text on the pages you visit. This policy explains what data we process and why.

1. Data we collect

Account: email address and password (handled via Google Firebase Authentication; we never have access to your password in plain text).
Usage data: number of translations performed, active plan and credits, to enforce free and premium plan limits.
Translated images: the page images you choose to translate are sent to our processing services in real time, only to extract and translate the text. We do not build profiles on what you read, and original images are not stored tied to your account.
Device identifier: a random identifier generated on your device at install time, used only to enforce free-plan daily limits and to prevent abuse (for example multiple accounts farming free credits). It is not linked to your real-world identity and is not used for advertising or for tracking you across websites.
Payments: handled entirely by Stripe. We do not store your card details.
Page address: when you translate, the address of the image and the address of the site you are reading on are sent to our servers, so the image can be retrieved and so hotlink-protected sites serve it. They are not stored with your account and are not used to build a reading profile.
Image download from your browser: when a site blocks downloads from our servers, the extension downloads the image from your own browser instead. That request goes to the site or content delivery network that already serves the same image to the page you are reading, and your browser attaches the session it already holds for that host, just as it does when the page itself loads the image. MangaLens never reads, stores or transmits your cookies: it has no access to them, and none of them reach our servers. Only the downloaded image is passed on for translation.
Series title and chapter: the extension reads them from the page. The title is sent with the translation request so that the title itself is not translated. If you connect AniList or MyAnimeList, title and chapter are also sent to that service — straight from your browser, not through us — to update your reading progress.
Recurring names: proper nouns and recurring terms found in the chapter you are reading are kept for the duration of that chapter and sent with the following pages, so that names stay consistent. They are discarded when you leave the chapter.

2. How we use data

Solely to provide the service: to authenticate you, enforce usage limits, process translations and manage subscriptions. We do not sell your data to third parties.

3. Third-party services

Google Firebase — authentication and account database.
Google Cloud Vision — text recognition (OCR) in images.
OpenAI — text translation (free plan and credits).
Anthropic Claude — high-quality translation (subscribers).
Stripe — payment processing.
AniList / MyAnimeList — reading-progress sync, only if you connect an account.

Images sent to these services are used only for real-time processing.

4. Data retention

We keep account data while you maintain an account. Processed translations may be cached anonymously to improve performance and reduce costs. If you delete your account we keep one thing: a one-way fingerprint of your email address, recorded only if your free trial had already started. It cannot be turned back into your address and it is not used to recognise you as a person — only to stop the same free trial being claimed again. Everything else is deleted.

5. Your rights

You can request deletion of your account and associated data by contacting us below.

6. Contact

For any privacy questions: mangalenss@gmail.com

Uninstall feedback

If you uninstall the extension, your browser may open a short optional form. If you choose to submit it, we collect the reason you selected, any free-text message you write, and — only if you provide it — your email address. This helps us improve MangaLens and, if you leave an email, lets us tell you when a problem you reported is fixed. The feedback is anonymous unless you include your email. To request deletion of feedback you submitted, email support@usemangalens.com.