The short version

• You can use the site without an account. Your progress then stays in your own browser.
• With an account, we store your email address and your learning progress.
• We don't sell your data, show ads or use analytics or tracking cookies.
• You can delete your account and everything in it at any time.

Information we collect

Without an account

Your progress, points and settings (such as dark mode and the song version you prefer) are saved in your browser's local storage, on your device only, and are never sent to our servers.

With an account

• Account details: your email address. If you sign up with a password, it is stored securely hashed by our authentication provider and we never see it.
• Google sign-in: if you continue with Google, Google shares your name, email address, profile picture and account ID with us. We only use them to sign you in and show who is signed in.
• Learning progress: the words, kanji and grammar points you mark as known and how you learned them, the songs you've started and the sessions you've finished, achievements, points, your daily goal and your time zone (so that days and streaks follow your own midnight).

When you sign in, any progress saved in your browser as a guest is copied into your account.

Error reports

When something goes wrong on the site, such as a page failing to load or progress failing to save, an error report is sent so we can fix it. It contains the error, the page you were on, your browser and operating system, and the steps that led to the error (such as the pages you opened). If you're signed in, it includes your account ID, but not your email address or name. It doesn't include your IP address or anything you typed.

When you contact us

If you use the contact form, we receive the name, email address and message you enter, and use them only to reply to you.

How we use it

Only to run the site: to sign you in, save and sync your progress between devices, calculate points and streaks, fix errors and answer your messages. We don't use your information for advertising, profiling or anything unrelated to learning on Uta Sensei.

Services we rely on

Some parts of the site are provided by other companies, who process data on our behalf:

• Supabase stores accounts and learning progress and handles sign-in.
• Netlify hosts the site and receives contact form messages. Like any web host, it processes your IP address to deliver pages.
• Google provides "Continue with Google" sign-in, under the Google Privacy Policy.
• YouTube plays the embedded song videos. When a video loads, YouTube may set cookies and collect information as described in the Google Privacy Policy.
• Sentry receives and stores error reports, in the European Union (Germany).
• Jotoba, a Japanese dictionary, is used to look up words, kanji and pronunciation audio. Your browser sends it the word being looked up, along with your IP address as with any web request. No account information is sent.

Cookies and local storage

We don't use tracking or advertising cookies. The site uses your browser's local storage to keep you signed in, to save guest progress and to remember your settings. Embedded YouTube videos may set their own cookies.

How long we keep it, and deleting it

We keep your account and progress for as long as your account exists. You can delete your account and all of its data yourself from your profile page; it's removed straight away. If you can't sign in, email uta_sensei@proton.me from the address you signed up with and we'll delete it within 30 days and confirm when it's done.

Guest progress lives only in your browser; clearing your browser's site data removes it.

Your rights

You can ask us for a copy of your data, to correct it or to delete it. Email us and we'll respond within 30 days. Depending on where you live, you may also have the right to complain to your local data protection authority.

Security

All traffic to the site is encrypted with HTTPS, and the database only lets each signed-in user read and change their own data. No system is perfectly secure, but we take reasonable care to protect your information.

Children

Uta Sensei is not directed at children under 13, and we don't knowingly collect their information. If you believe a child has created an account, contact us and we'll delete it.

Changes to this policy

If we change this policy, we'll update the date at the top of this page. Significant changes will also be announced on the site. See also our Terms of Service.