Privacy Policy

Last updated: March 2026

What we collect

Very little. When you use IsUp to check a website, our server makes an outbound HTTP request to that website on your behalf. We do not log the URLs you check, and we do not store your results on our server.

Server logs

Our web server (Nginx) keeps standard access and error logs. These logs may include your IP address, browser user-agent string, the page you visited, and the time of the request. Logs are used only for debugging and are rotated and deleted automatically. We do not analyze them for tracking purposes.

Cookies & sessions

IsUp uses a PHP session cookie to enforce rate limiting (preventing abuse of the checker). This cookie contains only a random session identifier. We do not use advertising cookies, tracking pixels, or any third-party analytics service.

Local storage

Your recent checks are saved in your browser’s localStorage so you can see them when you come back. This data never leaves your device. You can clear it at any time through your browser settings.

Third parties

We do not share any data with third parties. We do not run ads. We do not use analytics services.

Data security

All connections to IsUp are encrypted via HTTPS. We keep the server software up to date with security patches. The checker endpoint blocks requests to private and internal networks (SSRF protection).

Your rights

Since we do not collect or store personal data beyond transient server logs, there is typically nothing to request, correct, or delete. If you have questions, contact us at modularwebsystems@gmail.com.

Changes

If we change this policy, we’ll update the date at the top. Material changes will be noted on the homepage.