ContextLens is a Chrome extension that lets you highlight text or select a screenshot region on a webpage, receive an AI-generated explanation, and review saved explanations as history and flashcards. This policy explains what data is handled and how.
The following data may be stored locally in your browser using Chrome's
built-in storage API (chrome.storage.local):
When you ask ContextLens to explain or save something, the relevant selected text, screenshot region, recent tab audio (only when you use Listen), optional note, source URL/title for that selected item, chat context, and generated response may be sent over HTTPS to the ContextLens backend hosted on Railway. If you are signed in, saved highlights, screenshots, explanations, flashcard sets, and review metadata are stored in the ContextLens backend so they can sync across your devices.
ContextLens may also store first-party operational metrics such as feature event counts, success or failure status, coarse input type, model/provider used, and response latency. These metrics do not include raw highlighted text, screenshot image contents, notes, or full page browsing history, and are used only to monitor reliability, usage, and costs during beta.
ContextLens may use Google Analytics to understand aggregate extension usage, feature adoption, install attribution, performance, and errors. Analytics events may include event names, extension version, interface surface, coarse input type, success or failure status, latency bucket, and anonymous client/session identifiers. ContextLens does not send highlighted text, screenshot contents, notes, AI responses, source page URLs/titles, email addresses, passwords, or authentication tokens to Google Analytics.
When you create an account or sign in, your email address and password are sent over HTTPS to the ContextLens backend for authentication. If you choose Google Sign-In, Google may provide a verified email address to ContextLens so the backend can create or sign in to your account. The extension stores your email address and authentication token locally so it can keep you signed in. Passwords are not stored in the extension.
Paid ContextLens plans are billed as recurring monthly subscriptions through Stripe. Your payment card and billing details are collected and processed directly by Stripe under its own privacy policy; ContextLens receives only limited billing metadata (such as your plan, subscription status, and renewal date) and never your full card number. See our Terms of Service and Refund Policy for billing, cancellation, and refund terms.
ContextLens relies on the third-party providers below only to deliver the extension's core explanation, screenshot, account, sync, email, and payment features. We do not sell your data and do not use it for advertising.
When you request an explanation, the content you highlight — selected text, the screenshot image and any text extracted from it, your optional note, and your follow-up chat — is sent over HTTPS to third-party AI providers to generate the response. They process this content solely to return an explanation to you, and, per their current API terms, do not use content submitted through their APIs to train their models:
When you use the screenshot feature, the visible area of the current tab is captured so you can select a region. Only the selected region is sent for explanation. If you save the explanation or are signed in, the selected screenshot region and a smaller preview may be stored locally and in the ContextLens backend for history, review, and flashcards.
Listen is off by default and never starts on its own. The first time you use it, ContextLens asks you to confirm; once you start it, the extension records a rolling buffer of the current tab's audio. While it is running the ContextLens toolbar icon shows a red dot, and on supported video players a stop control appears in the player's own controls, so a capture is never running without a visible sign of it. Capture stops when you stop it, when you leave the tab, or when you close the tab.
The buffer is held on your device only. Nothing is sent anywhere until you ask for an explanation. When you do, the most recent 30 seconds to 5 minutes of that audio - whichever length you choose - is sent over HTTPS to the ContextLens backend and passed to our AI subprocessor to be transcribed and explained.
The audio itself is not stored. It is not written to the ContextLens database and is not retained after the explanation is produced. Only the resulting text - the transcription and the explanation - is saved, and only if you save it or are signed in. ContextLens does not use your microphone; Listen reads the audio the tab is already playing.
The extension requests the following Chrome permissions:
The use of information received from Google APIs will adhere to the Chrome Web Store User Data Policy, including the Limited Use requirements. ContextLens uses user data only to provide or improve its explanation, screenshot, history, sync, and flashcard features.
You can delete individual saved items from the ContextLens dashboard. Deleting a synced item removes it from local storage and requests deletion from the ContextLens backend. You can also delete your account from the dashboard or contact us for data deletion requests.
This extension does not knowingly collect data from anyone, including children.
If this policy changes, the updated version will be posted at this URL with a revised date.
Questions or data deletion requests? Email support@contextlens.co.