Privacy Policy

Last updated: March 2, 2026

Mnemonic is a browser extension that tracks your browsing activity locally to build a personal memory model. Privacy is central to how it works — your browsing data never leaves your device unless you explicitly choose to sync it.

This policy explains what data exists, where it lives, and the narrow set of information our server actually handles.

1. Data stored locally on your device

The extension stores the following in Chrome's local storage (chrome.storage.local) on your machine:

• URLs and page titles of sites you visit
• Text snippets and word counts from visited pages
• Engagement metrics: active time on page, visit count, scroll depth, event timeline
• Memory model parameters: stability score, retrievability, difficulty, growth factor
• Your blocklist configuration
• Extension settings and preferences

This data never leaves your device. We have no server infrastructure to receive it, no analytics pipeline to process it, and no way to access it. It exists only in your browser's local storage.

2. Data stored on our server

If you create an account (required for Pro features), our server stores:

• Email address — used for authentication (magic link login) and subscription-related emails
• Subscription status — whether you have an active Pro subscription, your plan type, and billing period
• Stripe customer ID — a reference ID that links your account to Stripe for payment processing
• Session tokens — temporary authentication tokens that expire automatically

That is the complete list. We do not store browsing data, memory entries, search queries, AI conversations, or any usage analytics on our server.

3. AI chat

The AI chat feature (Pro only) sends requests directly from your browser to the AI provider you choose (Anthropic, OpenAI, or Google) using your own API key. These requests include your question and relevant memory context.

Our server is not involved in AI chat at all. We never see your API key, your prompts, the memory context sent to the AI, or the responses you receive. Your relationship with the AI provider is governed by their own privacy policy and terms.

4. Obsidian vault sync

Vault sync (Pro only) writes markdown files to a local folder on your filesystem that you specify. This is a direct file write from the extension to your disk — no data passes through our server. If you sync that folder across devices using iCloud, Dropbox, or similar tools, that's between you and those services.

5. Third-party services

• Stripe — handles all payment processing. We never see or store your credit card number. Stripe's privacy policy applies to payment data. See stripe.com/privacy.
• Resend — delivers transactional emails (magic links, subscription confirmations). See resend.com/legal/privacy-policy.
• Cloudflare — hosts our backend and landing page. Standard request logs (IP address, timestamp) may be collected by Cloudflare's infrastructure. See cloudflare.com/privacypolicy.

6. Cookies and tracking

Our landing page does not use cookies, tracking pixels, analytics scripts, or any third-party tracking. We don't use Google Analytics, Mixpanel, Hotjar, or anything similar. The extension itself does not make any network requests except to check your subscription status (if logged in).

7. Data retention

• Local browsing data: Stays on your device until you uninstall the extension or clear Chrome's storage. You control it entirely.
• Account data: We retain your email and subscription records for as long as your account exists. If you ask us to delete your account, we will remove all server-side data within 30 days.
• Stripe data: Payment records are retained by Stripe according to their policies and applicable financial regulations.

8. Your rights

You can:

• View your local data at any time through the extension dashboard
• Delete your local data by uninstalling the extension or clearing site data in Chrome settings
• Export your data via vault sync (Pro) or the upcoming JSON export
• Delete your account by emailing us — we'll remove all server-side data
• Cancel your subscription at any time through the Stripe Customer Portal

9. Children's privacy

Mnemonic is not directed at children under 13. We do not knowingly collect information from children. If you believe a child has created an account, please contact us and we will delete it.

10. Changes to this policy

If we make material changes, we'll update the date at the top of this page and, if you have an account, notify you by email. Continued use of the extension after changes constitutes acceptance.

11. Contact

Questions about this policy? Email us at privacy@mnemonic.app.