Privacy policy
What ChatLang handles—and what stays on your device.
1. Purpose
ChatLang has one purpose: add language-learning aids to text you choose to read in the browser. These aids include pronunciation, romanization, word meanings, difficulty colors and optional percentage-based vocabulary replacement.
2. Data processed locally
The extension reads visible webpage text so it can identify supported scripts and render learning aids. Processing uses dictionaries packaged with the extension. Page text is not retained after the page closes and is not transmitted to our server.
Your preferences, per-site enablement and cached account/subscription state are stored in Chrome extension storage on your device. They remain until you clear extension data or uninstall ChatLang.
3. Google sign-in
Sign-in is optional for free local features and required for purchasing or restoring Pro. When you choose “Continue with Google,” Google provides an account identifier, verified email address, display name and optional profile image. The Google access token is sent to the ChatLang server only to validate the sign-in with Google; it is not stored by ChatLang. The server returns a time-limited ChatLang session token, which is stored locally by the extension.
4. Billing and subscription data
When you start checkout, ChatLang sends your verified account identifier, email address and selected plan to our server. Stripe receives the billing details you enter, processes payment and sends ChatLang the customer ID, subscription ID, plan, status and renewal/end date. ChatLang never receives or stores your full card number, security code or bank credentials.
5. Server and operational data
Our hosting provider may process standard request metadata such as IP address, request time and error information for security, delivery and troubleshooting. ChatLang does not use this infrastructure to build a browsing profile, record pages visited or collect page content. We do not use advertising trackers.
6. How data is used
- authenticate your account and prevent impersonation;
- create, verify, restore and manage your subscription;
- provide support, prevent abuse and keep the service reliable;
- comply with payment, tax, legal and security obligations.
7. Sharing and service providers
We share only the data necessary to provide the service with: Google, for optional account authentication; Stripe, for checkout, payment and subscription management; and Railway, for hosting the ChatLang account and billing API. Those providers process data under their own terms and privacy policies. We do not sell personal data, share it with data brokers or use it for targeted advertising.
8. Retention and deletion
Local extension data remains until you clear it or uninstall ChatLang. Account and subscription records are retained while your account or subscription is active and afterward only as required for billing, fraud prevention, dispute handling and legal compliance. You can delete eligible ChatLang account data from the Account tab after ending an active subscription. Stripe may retain payment records it or applicable law requires.
9. Security and choices
ChatLang uses signed, expiring sessions and verifies Stripe webhook signatures. You may use free local features without signing in, turn ChatLang off globally or per site, sign out at any time and manage or cancel a subscription through Stripe’s customer portal.
10. Changes and contact
Material changes will be posted on this page with a new effective date. For privacy questions or deletion requests, use ChatLang Support.