UptimeRobot IP Ranges
UptimeRobot checks whether a site is up by requesting it every few minutes from a pool of probe servers, and it publishes their addresses so that a firewall, a WAF or a rate limiter does not mistake the checks for an attack. On 16 October 2026 the IPv4 list held 103 single addresses. None of them is on a network UptimeRobot owns: they are rented servers at DigitalOcean, Hetzner, Amazon and Limestone Networks.
Known IP ranges
UptimeRobot has no network of its own. These are the probe addresses it publishes in uptimerobot.com/inc/files/ips/IPv4.txt, as fetched on 2026-10-16: 103 single hosts, spread across seven networks. DigitalOcean's AS14061 carries 36 of them, Hetzner 39 across three of its networks, Amazon 25, and Limestone Networks 3. WHOIS on any of them returns the hosting company; the list is what says it is UptimeRobot.
3.12.251.153/32
3.20.63.178/32
3.77.67.4/32
3.79.134.69/32
3.105.133.239/32
3.105.190.221/32
3.133.226.214/32
3.149.57.90/32
3.212.128.62/32
5.161.61.238/32
What does an UptimeRobot IP mean in a privacy test?
An UptimeRobot address in an access log is a monitor checking that the page answers. It is a robot on a rented server, not a visitor and not a VPN exit. If it is being blocked, the symptom is false downtime alerts: the site is up, but the probe cannot see it.
103 probes, seven networks
Every one of the 103 addresses was checked against the routing table. DigitalOcean's AS14061 announces 36. Hetzner announces 39 across three networks - 21 on AS24940, its dedicated-server network, and 18 on its cloud networks AS213230 and AS215859. Amazon announces 25, 19 on AS16509 and 6 on AS14618, and Limestone Networks' AS46475 the last 3.
That mix matters for anyone writing rules by network. Blocking data-center ASNs is a common bot-control tactic, and every one of these is a data-center ASN, so a WAF rule aimed at cheap VPS traffic will catch UptimeRobot's probes along with it. Exempting the 103 addresses individually, ahead of that rule, is the fix that does not open the door to everything else on those hosts.
Keeping the exemption narrow
The probes identify themselves with an UptimeRobot user-agent, but a user-agent can be copied by anyone; the address list is what confirms it. Exempt the listed addresses, not the networks they sit on: DigitalOcean and Hetzner rent servers to anyone, and the same ranges carry scrapers and scanners.
The list is a plain text file of addresses, one per line, with no date inside, and it changes as probes are added or moved. Refresh any rule built from it on a schedule.
Related tools
Frequently asked questions
What IP addresses does UptimeRobot use?
The 103 IPv4 addresses in uptimerobot.com/inc/files/ips/IPv4.txt, checked on 16 October 2026. They are single hosts on DigitalOcean, Hetzner, Amazon and Limestone Networks.
Why does an UptimeRobot IP appear in my logs or a privacy test?
An UptimeRobot address in an access log is a monitor checking that the page answers. It is a robot on a rented server, not a visitor and not a VPN exit. If it is being blocked, the symptom is false downtime alerts: the site is up, but the probe cannot see it.
Why is UptimeRobot reporting my site down when it is up?
Often because a firewall, WAF or rate limiter is blocking its probes. Every probe is on a data-center network, which is exactly what bot-control rules target. Exempt the published addresses ahead of those rules.
Does UptimeRobot have its own ASN?
No. Its probes run on rented servers: 36 on DigitalOcean's AS14061, 39 on Hetzner networks, 25 on Amazon and 3 on Limestone Networks, as checked on 16 October 2026.
Should I allowlist DigitalOcean or Hetzner for UptimeRobot?
No - allowlist the 103 addresses. Admitting the whole network would admit every other customer of that host, including the scrapers your rules are there to stop.