Autonomous System

AS21928

T-Mobile USA, Inc.

T-Mobile USA, Inc. United States 🌐 t-mobile.com

Announced IPs

13,187,328

CIDR prefixes

ASN

AS21928

Reputation · trust score

A transparent 0–100 signal. Every entity starts at a neutral baseline of 65; threat-intel blocklists, exposure, reverse-DNS, routing and allocation each adjust it up or down. Higher is more trustworthy.

67/100

Moderate

How this score is built

Baseline (neutral) 65
Mobile allocation +2
Trust score 67 / 100

Experimental · trust-vectors model v1.1.0 — a transparent heuristic, not a definitive verdict. How it works →

About T-Mobile US

T-Mobile US, Inc. is an American wireless network operator headquartered in Bellevue, Washington.

Founded

2001

Headquarters

Bellevue

Industry

telecommunications

Parent

Deutsche Telekom

Employees

38,000

Official website ↗ Summary from Wikipedia, CC BY-SA 4.0 · Data from Wikidata

Network profile

Source: PeeringDB →

Network type Cable/DSL/ISP

Geographic scope North America

Traffic ratio Mostly Inbound

Peering policy Selective

IRR record AS-21928

Present at 11 internet exchanges: SIX Seattle: MTU 1500, SFMIX, FL-IX, Any2West, NYIIX New York, Any2Denver, MICE: Shared Peering, Boston Internet Exchange, DET-iX, NWAX: Primary Peering VLAN, …

Website ↗

AS21928 — global IP footprint

Cities where AS21928 has measurable IPv4 allocation. Click any dot to open that city's page. Size and color scale with IP count.

View on 3D globe →

Top CIDR ranges

CIDR	IPs	PTR Density	Organization	Country	State	City
100.128.0.0/9	8.39M	0.0%	T-Mobile USA, Inc.	US	Washington	Seattle
100.160.0.0/11	2.10M	0.0%	—	US	—	—
162.160.0.0/11	2.10M	0.0%	T-Mobile USA, Inc.	US	Illinois	Chicago
172.32.0.0/11	2.10M	0.7%	T-Mobile USA, Inc.	US	Texas	Dallas
100.208.0.0/12	1.05M	0.0%	—	US	—	—
100.224.0.0/12	1.05M	0.0%	—	US	—	—
162.176.0.0/12	1.05M	0.0%	—	US	Illinois	Chicago
172.32.0.0/12	1.05M	0.0%	—	US	—	—
100.136.0.0/13	524.3K	0.0%	—	US	—	—
100.152.0.0/13	524.3K	0.0%	—	US	—	—
100.240.0.0/13	524.3K	0.0%	—	US	—	—
162.160.0.0/13	524.3K	0.0%	—	US	Indiana	Fort Wayne
172.48.0.0/13	524.3K	0.0%	—	US	—	—
100.132.0.0/14	262.1K	0.0%	—	US	—	—
100.144.0.0/14	262.1K	0.0%	—	US	—	—
100.192.0.0/14	262.1K	0.0%	—	US	—	—
100.204.0.0/14	262.1K	0.0%	—	US	—	—
100.248.0.0/14	262.1K	0.0%	—	US	—	—
162.168.0.0/14	262.1K	0.0%	—	US	Arizona	Prescott
172.60.0.0/14	262.1K	0.0%	—	US	—	—
74.60.0.0/15	131.1K	0.0%	T-Mobile USA, Inc.	US	—	—
75.122.0.0/15	131.1K	0.0%	T-Mobile USA, Inc.	US	California	Los Angeles
100.130.0.0/15	131.1K	0.0%	—	US	—	—
100.148.0.0/15	131.1K	0.0%	—	US	—	—
100.196.0.0/15	131.1K	0.0%	—	US	—	—
100.202.0.0/15	131.1K	0.0%	—	US	—	—
100.252.0.0/15	131.1K	0.0%	—	US	—	—
162.174.0.0/15	131.1K	0.0%	—	US	—	—
172.56.0.0/15	131.1K	0.0%	—	US	Georgia	Stone Mountain
65.76.0.0/16	65.5K	0.0%	T-Mobile USA, Inc.	US	California	Yorba Linda
74.60.0.0/16	65.5K	0.0%	T-Mobile USA, Inc.	US	—	—
100.129.0.0/16	65.5K	0.0%	—	US	—	—
100.151.0.0/16	65.5K	0.0%	—	US	—	—
100.198.0.0/16	65.5K	0.0%	—	US	—	—
100.201.0.0/16	65.5K	0.0%	—	US	—	—
100.255.0.0/16	65.5K	0.0%	—	US	Washington	Seattle
162.172.0.0/16	65.5K	0.0%	—	US	Connecticut	Hartford
167.20.0.0/16	65.5K	0.0%	T-Mobile USA, Inc.	US	Michigan	Saranac
168.73.0.0/16	65.5K	0.0%	T-Mobile USA, Inc.	US	Illinois	Chicago
170.206.0.0/16	65.5K	0.0%	T-Mobile USA, Inc.	US	North Carolina	Charlotte
172.58.0.0/16	65.5K	0.0%	—	US	Texas	Dallas
100.128.128.0/17	32.8K	0.0%	—	US	—	—
100.150.0.0/17	32.8K	0.0%	—	US	—	—
100.199.128.0/17	32.8K	0.0%	—	US	—	—
100.254.0.0/17	32.8K	0.0%	—	US	—	—
162.173.0.0/17	32.8K	0.0%	—	US	—	—
172.59.128.0/17	32.8K	0.0%	—	US	Ohio	Columbus
72.250.0.0/18	16.4K	0.0%	T-Mobile USA, Inc.	US	Texas	Dallas
100.128.64.0/18	16.4K	0.0%	—	US	—	—
100.150.128.0/18	16.4K	0.0%	—	US	—	—
100.199.64.0/18	16.4K	0.0%	—	US	—	—
100.200.64.0/18	16.4K	0.0%	—	US	—	—
100.200.192.0/18	16.4K	0.0%	—	US	—	—
100.254.128.0/18	16.4K	0.0%	—	US	—	—
162.173.128.0/18	16.4K	0.0%	—	US	—	—
172.59.64.0/18	16.4K	0.0%	—	US	Florida	Jacksonville
66.94.0.0/19	8.2K	0.8%	T-Mobile USA, Inc.	US	Washington	Seattle
100.128.32.0/19	8.2K	0.0%	—	US	—	—
100.150.192.0/19	8.2K	0.0%	—	US	—	—
100.199.32.0/19	8.2K	0.0%	—	US	—	—
100.200.32.0/19	8.2K	0.0%	—	US	—	—
100.200.160.0/19	8.2K	0.0%	—	US	—	—
100.254.192.0/19	8.2K	0.0%	—	US	—	—
162.173.192.0/19	8.2K	0.0%	—	US	—	—
172.59.32.0/19	8.2K	0.0%	—	US	Hawaii	Honolulu
208.54.96.0/19	8.2K	0.7%	T-Mobile USA, Inc.	US	New York	Rochester
208.54.128.0/19	8.2K	2.6%	T-Mobile USA, Inc.	US	Washington	Redmond
72.250.64.0/20	4.1K	0.0%	T-Mobile USA, Inc.	US	Missouri	Kansas City
72.250.96.0/20	4.1K	0.0%	T-Mobile USA, Inc.	US	—	—
100.128.16.0/20	4.1K	0.0%	—	US	—	—
100.150.224.0/20	4.1K	0.0%	—	US	—	—
100.199.16.0/20	4.1K	0.0%	—	US	—	—
100.200.16.0/20	4.1K	0.0%	—	US	—	—
100.200.128.0/20	4.1K	0.0%	—	US	—	—
100.254.224.0/20	4.1K	0.0%	—	US	—	—
162.173.240.0/20	4.1K	0.0%	—	US	—	—
172.59.0.0/20	4.1K	0.0%	—	US	New Mexico	Albuquerque
174.141.208.0/20	4.1K	1.8%	T-Mobile USA, Inc.	US	Michigan	Washington
208.54.0.0/20	4.1K	0.7%	T-Mobile USA, Inc.	US	California	Sacramento
208.54.48.0/20	4.1K	0.4%	T-Mobile USA, Inc.	US	Texas	Dallas
208.54.64.0/20	4.1K	0.2%	T-Mobile USA, Inc.	US	Alabama	Talladega
100.128.8.0/21	2.0K	0.0%	—	US	—	—
100.150.240.0/21	2.0K	0.0%	—	US	—	—
100.199.8.0/21	2.0K	0.0%	—	US	—	—
100.200.8.0/21	2.0K	0.0%	—	US	—	—
100.200.152.0/21	2.0K	0.0%	—	US	—	—
100.254.240.0/21	2.0K	0.0%	—	US	—	—
162.173.224.0/21	2.0K	0.0%	—	US	—	—
162.173.232.0/21	2.0K	0.0%	—	CA	—	—
172.59.24.0/21	2.0K	0.0%	—	US	Ohio	Cleveland
208.54.24.0/21	2.0K	0.8%	T-Mobile USA, Inc.	US	Washington	Seattle
208.54.40.0/21	2.0K	0.2%	T-Mobile USA, Inc.	US	District of Columbia	Washington
208.54.88.0/21	2.0K	0.5%	T-Mobile USA, Inc.	US	Pennsylvania	Philadelphia
100.128.4.0/22	1.0K	0.0%	—	US	—	—
100.150.248.0/22	1.0K	0.0%	—	US	—	—
100.199.4.0/22	1.0K	0.0%	—	US	—	—
100.200.4.0/22	1.0K	0.0%	—	US	—	—
100.200.144.0/22	1.0K	0.0%	—	US	—	—
100.254.252.0/22	1.0K	0.0%	—	US	—	—
104.152.20.0/22	1.0K	0.0%	T-Mobile USA, Inc.	US	—	—

BGP Announced Prefixes

Live BGP anomalies →

Prefixes AS21928 actually originates in BGP, observed across our RIPE RIS collectors. This live routing view can differ from the registry allocation above.

Prefix	Announcement samples	Last seen
208.54.34.0/24	24,923	2026-07-18 11:36:09
172.56.16.0/23	15,272	2026-07-18 12:18:42
172.56.208.0/21	14,548	2026-07-18 12:01:38
172.59.32.0/21	13,849	2026-07-18 12:18:42
172.56.186.0/23	12,736	2026-07-18 12:18:33
172.58.160.0/21	12,722	2026-07-18 12:01:37
172.56.54.0/23	12,671	2026-07-18 12:18:33
172.58.240.0/21	12,666	2026-07-18 12:18:36
172.59.120.0/21	12,315	2026-07-18 12:26:45
208.54.145.0/24	12,218	2026-07-18 11:36:09
172.56.216.0/21	11,977	2026-07-18 12:27:29
172.56.0.0/23	11,974	2026-07-18 12:18:24
172.59.16.0/21	11,960	2026-07-18 12:18:45
172.56.18.0/23	11,891	2026-07-18 12:18:24
172.56.8.0/23	11,662	2026-07-18 12:01:35
172.56.160.0/21	11,645	2026-07-18 12:18:45
172.59.128.0/21	11,527	2026-07-18 12:18:43
208.54.142.0/24	11,264	2026-07-18 11:36:09
172.58.208.0/21	11,085	2026-07-18 12:18:36
172.59.168.0/21	11,035	2026-07-18 12:01:37
172.56.176.0/21	11,016	2026-07-18 12:18:42
172.56.22.0/23	11,007	2026-07-18 12:01:35
172.56.232.0/21	10,995	2026-07-18 12:18:36
172.56.20.0/23	10,988	2026-07-18 12:01:35
172.56.120.0/21	10,936	2026-07-18 12:18:42
172.59.96.0/21	10,848	2026-07-18 12:01:37
172.56.248.0/21	10,817	2026-07-18 12:01:37
172.59.24.0/21	10,776	2026-07-18 12:18:44
172.58.112.0/21	10,720	2026-07-18 12:01:38
208.54.144.0/20	10,501	2026-07-18 11:36:09
172.56.32.0/23	10,410	2026-07-18 12:18:46
208.54.136.0/23	10,101	2026-07-18 11:36:09
172.56.64.0/21	9,939	2026-07-18 12:18:44
65.76.0.0/16	9,935	2026-07-18 11:59:58
162.187.128.0/17	9,632	2026-07-18 11:59:58
170.206.128.0/17	9,313	2026-07-18 12:01:37
172.56.34.0/23	9,281	2026-07-18 12:01:35
172.59.0.0/21	9,219	2026-07-18 12:01:38
172.59.112.0/21	9,172	2026-07-18 12:18:46
172.56.72.0/21	9,087	2026-07-18 12:01:36
66.94.17.0/24	8,969	2026-07-18 11:59:58
75.123.128.0/17	8,945	2026-07-18 11:59:57
75.122.128.0/17	8,588	2026-07-18 11:59:57
172.59.64.0/21	8,502	2026-07-18 12:18:42
172.56.96.0/21	8,497	2026-07-18 12:18:42
162.190.0.0/16	8,490	2026-07-18 11:59:58
172.56.240.0/21	8,454	2026-07-18 12:18:45
162.184.0.0/15	8,390	2026-07-18 11:59:58
172.56.224.0/21	8,248	2026-07-18 12:01:38
172.56.2.0/23	8,243	2026-07-18 12:01:35

Showing top 50 of 289 announced prefixes by sample volume.

Frequently Asked Questions

What is AS21928?

AS21928 is an Autonomous System Number assigned to T-Mobile USA, Inc.. An ASN identifies a network that controls a specific set of IP addresses and determines how traffic is routed across the internet via BGP (Border Gateway Protocol).

How many IP addresses does AS21928 announce?

AS21928 announces 13.19M IPv4 addresses distributed across 36 routed CIDR prefixes. The network is registered in United States.

Who operates AS21928?

AS21928 is operated by T-Mobile USA, Inc.. The organization is based in United States. You can view all IP ranges and related ASNs on the organization page.

What country is AS21928 registered in?

AS21928 is registered in United States. This indicates where the network operator is headquartered, though the IP addresses it announces may serve users globally.

Last updated: 2026-07-18 12:40:28 UTC