# IP addresses

The addresses Pulsefast checks come from, to allow them through firewalls and bot protection.


Pulsefast checks come from a few fixed addresses: one set per region. If your site sits behind a firewall, an allowlist, or bot protection (Cloudflare's bot fight mode, a WAF, rate limiting), let these addresses through, or checks may be blocked and show your site as down when it isn't.

- **List, one address per line:** [/ips](/ips)
- **JSON, by region, for scripts:** [/ips.json](/ips.json)

The list changes rarely, and never without notice to customers by email.

Checks also identify themselves with the user agent `Pulsefast/0.1 (+https://pulsefast.io)`, which some tools can allow instead of addresses.

**Cloudflare:** add the addresses to an IP Access rule with the action *Allow*, or a custom rule that skips bot protection for them.