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AS721
DNIC-ASBLK-00721-00726

AS721 announces 29,590,272 IPv4 addresses across 2,239 routed ranges, registered in US. Figures come from the public global routing table and are refreshed daily.

29.6M addressesIPv4 space announced
2,239Routed ranges
USRegistry country

Is AS721 datacenter space?

Not according to the nine cloud and CDN providers whose published range lists we track. That is a statement about those specific lists, not proof the space is residential — plenty of hosting companies never publish machine-readable ranges, and this AS may well be one of them.

The reliable way to classify a specific address is to check it directly rather than to infer from the AS. The free lookup tool returns live tunnel and datacenter signals for any address.

What an AS number does and does not tell you

An autonomous system number identifies who announces a block of addresses to the internet's routing table. It is an organisational fact, and a durable one — useful for attributing traffic to a hosting company, a carrier, or a university.

It is not a risk signal. A residential ISP's AS carries the household traffic of millions of ordinary customers and, at the same time, whatever residential proxy exits have been installed on those customers' devices. A hosting AS carries scrapers and legitimate server-to-server integrations in the same ranges. Scoring an address on the reputation of its AS produces exactly the false positives that make fraud tooling untrustworthy.

Sentinel does not feed AS names or routing data into its risk score. Tunnel detection comes from live network intelligence, and the dch signal comes from provider-published ranges. This directory exists to answer "who announces this address," which is a different and genuinely useful question.

Announced IPv4 ranges

First 100 of 2,239 ranges.

Range startRange endAddresses
6.16.172.06.16.174.255768
6.64.181.06.64.181.255256
55.0.0.055.0.255.25565,536
55.5.0.055.5.20.2555,376
55.5.22.055.5.242.25556,576
55.5.244.055.5.255.2553,072
55.9.0.055.9.255.25565,536
55.12.0.055.12.255.25565,536
55.14.0.055.14.255.25565,536
55.21.0.055.21.255.25565,536
55.29.0.055.29.255.25565,536
55.31.0.055.31.255.25565,536
55.33.0.055.33.255.25565,536
55.52.0.055.52.255.25565,536
55.57.0.055.57.255.25565,536
55.66.0.055.66.255.25565,536
55.76.0.055.76.255.25565,536
55.80.0.055.81.255.255131,072
55.99.0.055.99.255.25565,536
55.101.0.055.179.143.2555,148,672
55.179.146.055.179.229.25521,504
55.179.237.055.187.255.255529,152
55.189.37.055.189.39.255768
55.189.48.055.189.57.2552,560
55.189.60.055.189.63.2551,024
55.189.97.055.189.179.25521,248
55.189.181.055.190.1.25519,712
55.190.4.055.190.7.2551,024
55.190.9.055.190.79.25518,176
55.190.81.055.190.81.255256
55.190.83.055.190.83.255256
55.190.86.055.190.87.255512
55.190.89.055.190.96.2552,048
55.190.98.055.190.199.25526,112
55.190.201.055.190.253.25513,568
55.190.255.055.190.255.255256
55.192.0.055.193.255.255131,072
55.197.0.055.209.99.255812,032
55.209.101.055.209.199.25525,344
55.209.204.055.224.0.255931,072
55.224.2.055.224.6.2551,280
55.224.9.055.224.11.255768
55.224.32.055.224.63.2558,192
55.224.81.055.224.81.255256
55.224.83.055.224.85.255768
55.224.87.055.224.87.255256
55.224.89.055.224.95.2551,792
55.224.97.055.224.97.255256
55.224.99.055.224.102.2551,024
55.224.104.055.224.128.2556,400
55.224.135.055.255.255.2552,062,592
130.22.3.0130.22.6.2551,024
130.22.9.0130.22.9.255256
130.22.12.0130.22.20.2552,304
130.22.23.0130.22.25.255768
130.22.28.0130.22.31.2551,024
130.22.37.0130.22.46.2552,560
130.22.58.0130.22.62.2551,280
130.22.67.0130.22.67.255256
130.22.76.0130.22.87.2553,072
130.22.91.0130.22.91.255256
130.22.94.0130.22.94.255256
130.22.132.0130.22.142.2552,816
130.22.151.0130.22.161.2552,816
130.22.164.0130.22.175.2553,072
130.22.188.0130.22.188.255256
130.22.191.0130.22.191.255256
130.22.194.0130.22.251.25514,848
130.22.253.0130.22.255.255768
131.4.0.0131.5.47.25577,824
131.5.64.0131.5.255.25549,152
131.16.0.0131.16.79.25520,480
131.16.88.0131.16.255.25543,008
131.33.0.0131.33.119.25530,720
131.33.121.0131.33.255.25534,560
131.41.0.0131.43.8.255133,376
131.43.12.0131.43.13.255512
131.43.24.0131.43.27.2551,024
131.43.29.0131.43.29.255256
131.43.43.0131.43.45.255768
131.43.59.0131.43.61.255768
131.43.75.0131.43.77.255768
131.43.91.0131.43.109.2554,864
131.43.125.0131.43.125.255256
131.43.139.0131.43.141.255768
131.43.156.0131.43.157.255512
131.43.171.0131.43.189.2554,864
131.43.204.0131.43.205.255512
131.43.220.0131.43.221.255512
131.43.235.0131.43.237.255768
131.43.252.0131.43.255.2551,024
131.54.0.0131.54.255.25565,536
131.57.0.0131.57.255.25565,536
131.60.0.0131.60.9.2552,560
131.60.12.0131.60.13.255512
131.60.28.0131.60.29.255512
131.60.43.0131.60.45.255768
131.60.57.0131.60.61.2551,280
131.60.89.0131.60.109.2555,376
131.60.123.0131.60.123.255256

Check a specific address

The AS tells you who announces a range. Whether one address inside it is currently a tunnel is a live question, answered per address — for example 6.16.172.0, the first address in this AS's announced space. The free lookup tool takes any address, and the IP intelligence hub explains what each signal means.

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