AS27021 Quest Diagnostics, Inc.

AS-DGX - Quest Diagnostics, Inc. · registered in the United States

IPv4 addresses7,16810 prefixes · <0.001% of announced IPv4

Rank in United States#3,593largest network in US by IPv4 space, of 18,338 · <0.01% of US

Rank worldwide#11,542of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited States18,679 ASNs registered there

Open AS27021 in ASN lookup Look up an IP in this network (65.199.254.1) All networks in United States

IPv4 prefixes

All 10 prefixes, in address order.

65.199.254.0/24
156.30.5.0/24
156.30.24.0/24
204.235.142.0/23
209.242.240.0/23
209.242.247.0/24
209.242.248.0/24
209.242.250.0/23
216.195.72.0/24
216.203.80.0/20

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IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources