Nadinha Privacy Policy

Last updated: 19 October 2026

Nadinha is a browser extension and Mac app for learning languages. It translates words and phrases you choose on web pages and in video subtitles, saves them, and helps you review them with flashcards. This policy explains what data Nadinha handles and where it goes.

The short version

• Translation happens on your own computer. Text is only translated when you ask for it: when you hold ⌥ Option / Alt over a word, or highlight text.
• Words you save stay in your browser until you sign in. When you sign in (to use the dashboard at nadinha.com/app), your saved words, flashcard progress and settings are stored in your account so they're the same on every computer.
• We don't sell your data, show ads, or use analytics or tracking.

What Nadinha stores on your device

Stored only in your browser (Chrome's extension storage):

• Words and phrases you look up or save, with their translations
• The sentence or subtitle line each saved word came from, and the title and address of that page, so your flashcards can show the original context
• Your flashcard review history and settings

You can delete individual words in the dashboard, or remove everything stored in the browser by uninstalling the extension. You can export your words at any time.

While you watch a video with subtitles, Nadinha keeps the recent subtitle lines in memory on that tab so the optional AI tutor can answer questions about the scene. These lines are not saved and are cleared when you leave the page.

Your account (only if you sign in)

To use the dashboard you create an account, with Google or with an email address and password. We then store:

• your email address and how you signed in;
• your saved words and phrases, their translations, the sentence each came from, and the title and address of that page or the name of the app it came from;
• your flashcard progress and your settings;
• whether you asked for tips and updates by email (off unless you tick the box).

This is stored by Supabase, our database and sign-in provider, on servers in London (UK). It's used only to run Nadinha for you: showing your dashboard and keeping your words in step between the extension, the desktop app and your other computers. If you sign in with Google, Google tells us your email address and name; we don't get your Google password.

You can export your words at any time. Delete my data in the dashboard's settings permanently deletes your words, flashcard progress and settings. To also close your sign-in account, email hello@nadinha.com and we'll delete it.

The website itself is hosted by Vercel.

What is sent off your device, and when

Translation. When you look up a word or phrase:

Translation happens on your computer, using Chrome's built-in translator. If you turn on better phrase translations, Chrome's built-in language model (Gemini Nano) runs on your computer too. Either way, the text isn't sent anywhere.

If you use the Nadinha Mac app, it asks the Nadinha extension in Chrome to translate the text you point at. This happens entirely on your own computer, over a private local connection.

AI tutor (only when you ask it something). When you ask the tutor a question, Nadinha sends your question, the title of the page you're on, the recent subtitle lines or text you highlighted, the word you asked about, and a list of your recent saved words to Anthropic, which makes the Claude model that writes the answer.

It goes through Nadinha's server (run on Supabase), which checks your monthly allowance and counts the question. We don't keep the questions or answers; we only keep the count. Anthropic processes the request under its commercial terms and doesn't use it to train its models.

Payments (Premium only). If you subscribe, payment is handled by Stripe on its own secure checkout page. Your card details go to Stripe, never to Nadinha. Stripe tells us whether your subscription is active, and we store your Stripe customer number so you can manage or cancel it.

Apart from your account, the tutor and payments (above), nothing is sent to us, the makers of Nadinha.

The Mac app

The Nadinha Mac app uses macOS Accessibility permission, which you switch on yourself, to read the word under your pointer while you hold ⌥ Option, or text you've highlighted. It doesn't read the screen at any other time and doesn't record keystrokes or take screenshots. Words you save are kept on your Mac (in your Library folder) and, while Chrome is open, added to your deck in the extension over a private local connection; from there they reach your account if you're signed in.

What Nadinha does not do

• It does not read pages in the background. It only looks at the text under your cursor or that you highlight, plus subtitle lines on pages with video (kept in memory for the AI tutor, as described above).
• It does not collect passwords or form contents. Card details for Premium go to Stripe, not to Nadinha.
• It does not sell or transfer data to third parties, except the translation, AI tutor and payment requests you trigger, described above.
• It does not use data for advertising, credit decisions, or any purpose unrelated to language learning.

The use of information received from Google APIs complies with the Chrome Web Store User Data Policy, including the Limited Use requirements.

Children

Nadinha is not directed at children under 13 and we do not knowingly collect information from them.

Changes

If this policy changes, we'll update the date above and describe the changes in the extension's release notes.

Contact

Questions about privacy: hello@nadinha.com