Privacy Policy

Last updated: October 14, 2026

This policy explains what information Kitsui ("we", "us") collects when you use thekitsui.com, how we use it, and the choices you have. Kitsui is a language-learning tool that lets you translate words and phrases, save flashcards and study them with spaced repetition.

1. Who we are

Kitsui is operated by Kitsui. You can contact us at kitsui547@gmail.com.

2. Information we collect

• Account information. When you sign in with Google, we receive your name, email address and profile picture from Google, and we create an account identifier for you.
• Content you create. Decks, flashcards (words, readings, meanings and example sentences you save) and your study progress, such as review dates, intervals and your answers to cards.
• Text you translate. The words or phrases you type into the translator are sent to our server and then to Google's Gemini API, which generates the translation, readings and examples.
• Data stored in your browser. Your last search, language choices, selected deck, a cached copy of your decks and study counters are kept in your browser's local storage on your own device.
• Technical information. Our hosting and database providers may automatically record your IP address, browser and device type, and request times in server logs.

3. How we use your information

• To let you sign in and keep your decks, cards and progress in your account.
• To translate the words and phrases you submit and to generate flashcard content.
• To schedule your reviews and show your learning progress.
• To keep the service secure, fix problems and understand how the site is used.
• To show advertising that helps pay for the service (see section 5).

We do not sell your personal information.

4. Service providers we share data with

We use the following providers to run Kitsui. They process data on our behalf:

• Supabase – account login and database where your decks and cards are stored.
• Render – hosting of the website and server.
• Google – Google Sign-In, the Gemini API used for translations, and Google AdSense for ads.

These providers have their own privacy policies and may process data in countries other than your own.

5. Cookies, local storage and advertising

We use browser local storage to remember your settings and to speed up loading, as described above. Signing in also uses cookies or similar storage to keep you logged in.

We may show ads provided by Google AdSense. Google and its partners may use cookies to serve ads based on your visits to this and other websites. You can opt out of personalized advertising in Google Ads Settings, and you can read how Google uses data from sites that use its services at policies.google.com/technologies/partner-sites.

6. How long we keep your data

We keep your account, decks, cards and progress for as long as your account exists, or until you ask us to delete them. Server logs are kept by our hosting providers for limited periods.

7. Your rights and choices

You can ask us to access, correct, export or delete the personal information we hold about you, including your account and all of your flashcards, by emailing kitsui547@gmail.com. Depending on where you live (for example under the GDPR in the EU and UK, the LGPD in Brazil or the APPI in Japan), you may have additional rights. You can also clear the data stored in your browser at any time from your browser settings.

8. Children

Kitsui is not intended for children under 13 (or under the minimum age required in your country), and we do not knowingly collect their personal information. If you believe a child has given us information, please contact us and we will delete it.

9. Changes to this policy

We may update this policy from time to time. When we do, we will change the "Last updated" date at the top of this page.

10. Contact

Questions about this policy or your data? Write to kitsui547@gmail.com.