Here’s the list of all our Uptime Monitoring IP Addresses.

New York:
52.207.41.187
96.126.106.201
52.23.120.125
138.197.17.201
66.165.247.154
149.28.50.248
172.241.23.225
209.222.107.178
23.226.128.254

San Francisco:
23.239.7.4
52.52.33.209
149.28.212.239
159.89.159.134
66.165.225.34
23.108.190.195
104.149.137.26

Dallas:
104.237.139.48
45.32.204.172
23.227.169.50
172.241.24.83
45.35.33.30

Amsterdam:
95.179.139.97
51.15.61.222
188.166.79.172
37.48.96.90
172.107.226.134
51.158.156.63

London:
52.56.73.124
139.162.228.62
95.179.193.59
178.62.11.90
51.195.149.151
23.106.61.94
172.107.96.66
103.50.32.15

Frankfurt:
52.59.92.96
78.46.88.58
94.16.112.18
51.195.46.219
178.162.208.86
192.248.181.140
91.239.130.97

Singapore:
52.221.91.160
139.162.22.205
128.199.187.77
45.76.150.238
51.79.156.91
23.106.120.205

Sydney:
52.65.182.14
45.76.120.140
139.99.169.250
172.105.168.58
172.107.229.6

Sao Paulo:
52.67.204.189
104.41.61.219
35.199.108.206
216.238.100.86
189.1.173.35

Tokyo:
52.199.17.123
45.76.202.144
172.104.99.63
172.107.201.78

Mumbai:
35.154.5.38
104.211.188.46
172.105.37.103
103.78.121.138

Warsaw:
146.59.0.13
70.34.249.133
5.22.223.148

We also always keep updated this text list of our Uptime Monitoring IPs:
https://hetrixtools.com/resources/uptime-monitor-ips.txt
And just IPs here:
https://hetrixtools.com/resources/uptime-monitor-only-ips.txt

Learn what steps are taken when the uptime monitoring infrastructure changes:
https://docs.hetrixtools.com/how-do-we-perform-uptime-monitoring-network-changes/