Luna privacy policy

Effective October 24, 2026. Luna is a browser extension made by XT3 LLC.

Short version: Luna has no ads, no analytics and no tracking, and we never sell data. Luna reads only the text you select, and sends it only when you ask for a translation: the selection, a little of the text around it and the page title go to Luna's server (or straight to OpenAI if you use your own key) so the AI can write the answer. Your Luna account keeps your email, your settings, your saved words and how many translations you've used, so they follow you between browsers. You can export or delete all of it.

What Luna sends, and when

Nothing leaves your browser until you ask Luna for something: clicking the moon or a button in Luna's toolbar, pressing Alt+L, or choosing Luna in the right-click menu. Then Luna sends:

• The text you selected (up to 6,000 characters) and up to about 400 characters of the text around it, so it can tell which meaning is meant.
• The page title and site name (for example "es.wikipedia.org"), for the same reason.
• Your language settings: the languages you know, the one you're learning and your level, so the answer is written for you.

Where it goes depends on your plan:

• Free and Luna Pro: to Luna's server at luna.xt3.us, which asks OpenAI to write the answer and passes it back to you. The server does not keep the text you selected or the answer. It records that a request happened (the day, how many requests, how many AI tokens they used) to count your free translations and keep the service fair.
• Luna Own Key: straight from your browser to OpenAI (api.openai.com) with your own API key. Luna's server never sees the text.

Luna asks OpenAI not to store its answers. OpenAI processes what it receives under its own API data policies.

Immersion (off unless you turn it on): on pages written in a language you know, Luna sends a sample of the page's text (up to 4,000 characters) to choose a few words to swap for the language you're learning.

Your Luna account

You sign in with Google (or with a one-time code sent to your email, where offered). Google sign-in asks Google only for your email address (the openid and email scopes); Luna receives your email and Google's ID number for your account, nothing else from Google. An emailed code is sent through an email delivery service and expires after 10 minutes.

Your account stores:

• your email address and Google account ID number;
• your settings (languages, level and display choices);
• your saved words, each with its translation, review schedule, and the address and title of the page you saved it from;
• your usage counts: translations used per day and the AI tokens they took;
• your plan: the Gumroad license key you entered, which plan it is for, and whether Gumroad says it is active.

Settings and saved words sync between your browsers through the account: soon after a change, and every 30 minutes.

Plans and payment

Luna Pro ($20 a month) and Luna Own Key ($10 a year) are memberships sold by XT3 on Gumroad (shop.xt3.us). Gumroad handles the payment and Luna never sees your card. When you buy, Gumroad tells Luna's server the email address you bought with and your license key, so the plan can be matched to your account when you sign in. When you enter a key in Luna's settings, and from time to time after that, Luna's server checks it with Gumroad's license API to see that the membership is still active. Gumroad's privacy policy covers the purchase itself.

What stays in your browser

• Your settings, in the browser's extension storage (chrome.storage.sync; if you use your browser's own sync, your browser may carry them to your other computers too).
• Your saved words, your sign-in session, and recently shown answers (kept up to 7 days so the same selection opens instantly), in chrome.storage.local.
• Your OpenAI API key (Own Key plan): kept in Luna's private storage in your browser (the extension's own IndexedDB, which web pages and Luna's in-page script cannot read), used only by Luna's background service worker, and sent only to OpenAI. It never goes to Luna's server, is never synced or exported, and is removed from the browser when you sign out of Luna.

Other things to know

• Read aloud uses your browser's built-in voices. Some browser voices are provided online by your browser's maker, in which case the browser sends them the text to speak.
• Writing to us: if you email ian@xt3.us, we see what you send.
• After removing Luna: your browser opens a short goodbye page at https://luna.xt3.us/bye. It receives Luna's version number and nothing else.
• Luna does not load or run remote code. Answers from the AI are data that Luna shows as text.

What we don't do

No advertising, no analytics, no crash reports, no tracking pixels, no selling or sharing of data with data brokers. Data is used only to run Luna: to write your answers, keep your account, count your free translations and check your plan. It is not used for creditworthiness or lending, and it is not used to train AI models.

Who receives data

• OpenAI, to write answers (directly from your browser on Own Key, through Luna's server otherwise).
• Google, when you choose to sign in with Google.
• Gumroad, for purchases and license checks.
• Our hosting and email providers, which run Luna's server and deliver sign-in codes on our behalf.

Your control

• Export: Settings › Privacy & data › Export my data downloads everything as JSON (settings, saved words and your account data). Saved words also export as CSV (Settings › Saved words).
• Delete: Settings › Privacy & data › Delete account deletes your account, saved words, usage history and license record from Luna's server. "Clear everything on this device" removes Luna's data from this browser. Removing the extension deletes its data from the browser.
• Turn it off: switch Luna off for any site from the toolbar button, or set "When I select text, show" to Nothing.
• Your Gumroad membership is managed (and cancelled) on Gumroad.

Children

Luna is not directed at children under 13 and we do not knowingly collect data from them.

Changes

If this policy changes, the new version will be posted on this page with a new date.

Questions or requests: ian@xt3.us. A real person answers.