✨ ToneShift — Privacy Policy

Last updated: June 2026

1. Overview

ToneShift ("the Extension") is a Chrome browser extension that helps you rewrite and generate text using AI. This Privacy Policy explains what data we handle and how.

2. Data We Collect

ToneShift does not collect any personal data. Specifically:

• We do not collect your name, email address, or any account information.
• We do not track your browsing history or the websites you visit.
• We do not store the text you write or have rewritten.
• We do not use analytics or tracking services.

3. Data Stored Locally

The following data is stored only on your local device using chrome.storage.local:

• Anthropic API Key — Your API key, entered in the Settings page. It never leaves your device except to make direct API calls to Anthropic.
• Extension preferences — Default tone, enabled/disabled sites, custom tones.
• Usage counter — A daily rewrite count used to enforce the free tier limit. Stored locally and resets daily.
• Pro status — Whether your account has an active Pro subscription (checked via ExtensionPay).

4. Third-Party Services

Anthropic API

When you use ToneShift to rewrite or generate text, your input text is sent directly from your browser to Anthropic's API using your own API key. Please refer to Anthropic's Privacy Policy for information on how they handle API requests.

ExtensionPay

Pro subscription management is handled by ExtensionPay. When you subscribe, payment processing and subscription status are managed by ExtensionPay. Please refer to ExtensionPay's Privacy Policy for details.

5. Permissions Used

ToneShift requests the following browser permissions:

• activeTab — To interact with the current tab's content (show the floating button).
• storage — To save your settings and API key locally.
• scripting — To inject the writing assistant UI into supported pages.
• Host permissions for Gmail, LinkedIn, Twitter/X — To activate the extension only on these specific sites.
• api.anthropic.com — To send API requests directly from your browser to Anthropic.

6. Data Security

Your Anthropic API key is stored in Chrome's local storage, which is sandboxed to this extension and not accessible by websites or other extensions. We recommend keeping your API key confidential and regenerating it if you believe it has been compromised.

7. Children's Privacy

ToneShift is not directed at children under 13. We do not knowingly collect data from children.

8. Changes to This Policy

We may update this Privacy Policy from time to time. Changes will be reflected by the "Last updated" date above. Continued use of the extension after changes constitutes acceptance of the updated policy.

9. Contact

If you have questions about this Privacy Policy, please contact us at: m.masaki.sm@gmail.com