Privacy Policy

Who we are

This website, mastertool.dev ("MasterTool", "we", "us"), provides free online calculators and converters. You can contact us about privacy at contact@mastertool.dev.

Our core commitment

All MasterTool tools run 100% locally in your web browser. Data you enter into any tool is never transmitted to, stored on, or accessible from any server operated by MasterTool. MasterTool has no user accounts and no database of tool inputs.

What data we collect

Tool inputs: not collected. Calculations happen on your device and disappear when you leave or reload the page.

Email: if you contact us by email, we receive your email address and the content of your message. We use this only to reply to you and keep it only as long as needed to handle your enquiry.

Server logs: like any website, our hosting provider may process standard technical request data (such as IP address, browser type and the page requested) to deliver pages and protect against abuse. These logs do not contain tool inputs.

Cookies and local storage

We group cookies and similar technologies into three categories:

• Strictly necessary — required for the site to work, including remembering your cookie choices. Always active.
• Analytics — measure page usage in aggregate. Used only if you consent.
• Advertising — allow ad partners to show and personalise ads. Used only if you consent.

See our Cookie Policy for the exact items we set, and change your choices any time in Cookie Settings.

Analytics

If analytics is enabled on the site, it runs only after you give analytics consent, measures page usage in aggregate, and never receives tool input data. At the time of writing no analytics service is active.

Advertising

If advertising is enabled, third-party ad partners may use cookies for ad personalisation only after you give advertising consent. You can withdraw consent at any time through Cookie Settings. At the time of writing no advertising service is active.

Third-party services

The site loads web fonts from Google Fonts, which receives your IP address and browser information in order to deliver font files. No tool input is shared with any third party.

Data retention

Your cookie preference is stored in your browser until you clear it or change it. Emails are retained only as long as needed to resolve your enquiry and then deleted.

Your rights

UK and EU visitors (GDPR / UK GDPR): you have the right to access, correct and delete personal data we hold about you, to object to or restrict processing, and to lodge a complaint with your supervisory authority.

California residents (CCPA/CPRA): you have the right to know what personal information we collect, to request deletion and correction, and to opt out of the sale or sharing of personal information. We do not sell personal information. To exercise "Do Not Sell or Share My Personal Information", choose "Reject Non-Essential" in Cookie Settings, which disables advertising cookies.

To exercise any right, email contact@mastertool.dev. We will respond within the time required by applicable law.

Children's privacy

MasterTool is not directed at children under 13, and we do not knowingly collect personal information from children.

Changes to this policy

We may update this policy. The "Last updated" date above shows when it last changed; significant changes will be highlighted on this page.

Contact us

Questions about privacy: contact@mastertool.dev.