Explainish is a Chrome extension that helps you understand web content using Google's Gemini AI. This policy explains exactly what data is collected, how it is used, and what is never collected.
Explainish processes all AI requests directly between your browser and Google's Gemini API using your own API key. No content ever passes through any server operated by Explainish. The table below shows exactly what data is sent for each feature:
| Feature | Data sent to Gemini | Destination |
|---|---|---|
| Summarize | Page title, URL, and visible page text (up to ~12,000 characters). Google Search grounding may be enabled, meaning Google may perform searches based on your page content. | Google Gemini API |
| Explain / Simplify | Your highlighted text and, on non-restricted sites, a short surrounding passage (~400 characters) for context. Google Search grounding is enabled, meaning Google may perform web searches to provide more accurate responses. | Google Gemini API |
| Define | Your highlighted text and surrounding context (same as Explain). Google Search grounding is enabled. | Google Gemini API |
| Chat follow-ups | Your question, prior conversation messages, and page text (first message only). Google Search grounding is enabled. | Google Gemini API |
| Restricted sites | Highlighted text only — no page content, no surrounding context. Webmail, banking, healthcare, and government portals are restricted by default. | Google Gemini API |
Your API key is transmitted to Google's Gemini API via a secure HTTP header (x-goog-api-key), never as a URL parameter. The key is stored only on your device and is never transmitted to Explainish.
Gemini API usage is governed by Google's API Terms of Service and Google's Privacy Policy.
Explainish collects anonymous usage analytics to understand how the extension is used and improve it over time. Analytics are opt-out and can be disabled at any time in Settings. This includes:
A randomly generated UUID created at install time and stored locally on your device. It is not linked to your name, email, or any personal identity.
Actions such as opening the panel, summarizing a page, using the explain, simplify, or define tooltip, sending a chat message, and progressing through the initial setup flow. When an API request fails, a generic error code (e.g. "rate limit") is also logged. These events include only the action name, general parameters (e.g. step number, action type, error code), and a random session identifier. No page content, highlighted text, or personally identifiable information is included.
The hostname only (e.g. example.com), not the full URL, page content, or browsing history.
A content category inferred from the domain (e.g. "news", "tech", "academic"). Derived locally; the full domain list is not transmitted.
The number of prompt and response tokens consumed per Gemini API call. Used to understand typical usage scale. No content is included.
How often the extension is opened, days since install, and total session count. Calculated locally and transmitted as aggregate numbers.
Analytics events are sent from your browser to Google Analytics via the Measurement Protocol. We do not operate a server that receives or stores this data. Google Analytics may collect technical information such as IP address and browser metadata under its own privacy practices, described at policies.google.com/privacy.
The following data is stored locally in your browser using chrome.storage.local and never transmitted to Explainish servers:
Stored only on your device. Used exclusively to make requests directly from your browser to Google's Gemini API.
The randomly generated installation ID described above.
First-seen date, last-seen date, total session count, and per-domain usage counters. Used to calculate retention signals locally before transmission.
Any domains you have added to or removed from the auto-summarize allow list or block list.
A built-in list of domains (webmail, banking, healthcare, government) distributed to content scripts via local storage. This list is not transmitted externally.
Explainish requires a Google Gemini API key to function. This key is stored exclusively in your browser's local storage on your own device. It is never transmitted to us, never stored on any server, and never shared with any third party. Its only purpose is to authenticate direct requests from your browser to Google's Gemini API.
Explainish includes a built-in list of sensitive domains — webmail providers, banks, healthcare portals, and government sites — where auto-summarize is paused and tooltip actions send only highlighted text, never surrounding context. This protects against inadvertent exposure of private information. You can override these defaults on a per-site basis in Settings.
Explainish runs a content script on every web page you visit. This script enables two features: the text-selection tooltip (Explain, Simplify, Define) and page content extraction for the Summarize feature. The content script does not automatically send any data to external services — data is only transmitted when you take an explicit action, such as highlighting text and clicking a tooltip button, or opening the side panel.
On sensitive sites (webmail, banking, healthcare, and government portals), the content script restricts its behavior automatically: auto-summarize is paused and tooltip actions send only your highlighted text, with no surrounding page context. You can customize these protections per-site in Settings.
We do not sell, rent, or share your data with any third party. Anonymous analytics data flows to Google Analytics solely to help us understand and improve the extension. No personally identifiable information is ever shared.
Analytics data is retained in Google Analytics for 14 months, after which it is automatically deleted. We do not store page content, prompts, AI responses, or API keys. Local device data (preferences, session counters) persists until you uninstall the extension or clear your browser storage.
Depending on your jurisdiction, you may have rights regarding access, correction, or deletion of personal data. Because Explainish does not collect personally identifiable information, we are generally unable to associate analytics data with any specific individual. If you have questions or requests regarding your data, please contact us via the support email listed on our Chrome Web Store page.
Explainish is not directed at children under the age of 13. We do not knowingly collect any information from children.
If we make material changes to this policy, we will update the date at the top of this page. Continued use of the extension after changes constitutes acceptance of the updated policy.
If you have any questions about this privacy policy, please contact us via the support email listed on the Chrome Web Store listing page.