your data stays yours.

the short version

• your progress, saved words and settings stay in your browser. we never see them.
• there's no account and we don't collect your email. cross-device sync is coming and will be optional.
• hanzen is free. there is no payment, so there is no card data anywhere.
• we do not sell your data and we do not run ad tracking.

who we are

hanzen is an independent product made by one small team. you can reach us any time at support@hanzen.app.

what we collect

your study data (stays on your device)

your progress, the scenes you've seen, saved words and settings are stored inside your browser on the device you use. they don't leave it.

cross-device sync (coming later)

right now there's no sign-in and no account, so we never see your email or your study data. when optional cross-device sync ships, you'll be able to turn it on to keep your progress in step across devices, and we'll update this page before it does.

hanzen watch (the chrome add-on)

hanzen watch works on youtube and bilibili. its settings, saved words and study data live in the add-on's own storage on your computer, and your study is never sent to us. the one exception: if you enter a pro key, the add-on sends that key, and nothing else, to hanzen.app to confirm it's still valid, at most once a day. free users enter no key, so nothing goes to us at all.

on a video you are watching, the add-on reads the chinese caption track from youtube or bilibili so it can break down each line. those requests fetch text to show you and carry none of your study data. the add-on has no analytics, no ads and no tracking.

other services in the loop

• dexie cloud is the provider we'll use for optional cross-device sync when it launches. until then, nothing is sent to it.
• vercel hosts this website and the app. like any web host, it handles standard request data such as your ip address to serve pages.
• youtube and bilibili serve the captions hanzen watch reads. their own privacy policies cover those requests.
• hanzen.app gets a pro key check only if you entered a key: the key alone, to confirm it's valid. no key means no request.

that's the whole list. no advertising trackers, no analytics on your study.

what we don't do

• we don't sell your personal data to anyone.
• we don't share your study data with advertisers.
• we don't need an account to use the app or the add-on.

your choices

everything stays on your device. to clear it, clear the site's storage in your browser or remove the add-on. depending on where you live, you may have rights to see, fix or delete any personal data we hold. email support@hanzen.app and we'll help.

how long we keep things

your study data stays on your device until you clear it.

children

hanzen is not aimed at children under 13, and we don't knowingly collect data from them.

changes

if the way hanzen handles data changes, we update this page and the date at the top. for a big change we do our best to say so in the app.

contact

questions about privacy? email support@hanzen.app.