Round-Trip Time

Deep dive into network latency on the web: an interactive report based on Round-Trip Time (RTT) data from Chrome UX Report (CrUX).

Overview

This is an interactive report to explore network latency on the web. It addresses questions such as: What is the current health of the network? How does it vary by country and website categories? It uses Round-Trip Time (RTT) data from Chrome UX Report (CrUX).

RTT shows the time it takes for a request to go from a client to the server and back (round-trip). In CrUX, it is estimated on the initial page load navigation using navigator.connection.rtt and measured in milliseconds. CrUX provides 75th percentile (p75) aggregated for all domain visits during the past 28 days.

RTT is a diagnostic metric that helps you to understand your audience network connection. Instead of relying on 2G, 3G, or 4G labels (which are also based on RTT), it provides better visibility to your visitors' connection. For example, if your site's average RTT is slow, performance metrics like TTFB or LCP are also likely to be impacted. Consider loading some parts of your site conditionally (learn more). But if RTT is fast and you still have slow metrics, you need to optimize your site. We tried to define fast & slow buckets on the map below. To measure your site's performance, use our free Site Speed Test.

Methodology: we took RTT data for the top 50,000 domains aggregated during February 2025 (excluding empty values, which resulted in 49,808). Here are the median (p50) values by device type:

Mobile
151ms
Desktop
95ms
All Devices
138ms

Usually, 70% of a website's traffic is mobile, which explains why the All Devices value is closer to Mobile than Desktop. The table below provides a detailed breakdown of the RTT distribution with percentiles and statistics:

Desktop
65ms
75ms
95ms
126ms
174ms
30ms
109ms
1295ms
40,946
All Devices
83ms
102ms
138ms
195ms
264ms
29ms
158ms
1684ms
49,808
Mobile
95ms
116ms
151ms
209ms
270ms
29ms
171ms
1685ms
48,851

Geography

Let's explore RTT by country. The regional difference is clear and reflects countries' GDP and the location of data centers. Australia and New Zealand famously experience higher RTT due to speed of light limitations, as data centers are primarily located in the US and Europe. We computed regional RTT using top-level domains (TLDs). For example, .nl represents the Netherlands, and .ca is Canada.

The map below displays the median RTT (p50). And the table on the right lists the top 10 fastest and slowest countries. You can interact with the map and use the device switch to change aggregation.

<100ms
100–150ms
150–200ms
200–250ms
>250ms
Rank
Country
p50
1.
Taiwan
51ms
2.
Netherlands
53ms
3.
Switzerland
57ms
4.
Sweden
58ms
5.
Norway
61ms
6.
Denmark
65ms
7.
Germany
66ms
8.
Czechia
66ms
9.
Japan
67ms
10.
Belgium
67ms
...
...
...
61.
Egypt
163ms
62.
Venezuela
177ms
63.
Algeria
177ms
64.
Saudi Arabia
184ms
65.
South Africa
189ms
66.
Kenya
219ms
67.
Sri Lanka
237ms
68.
Iran
238ms
69.
Pakistan
245ms
70.
Nigeria
357ms

Categories

The network latency varies up to 50% by website category. Sectors like E-commerce or Auto-industry tend to invest more in web performance, resulting in lower RTT. In contrast, categories like Entertainment or Adult content, are much slower. To classify websites, we used Chrome's topic classifier (chrome://topics-internals/). Below is an interactive table to explore the network latency across different clusters of the web:

Food & Drink
60.5ms
69ms
78ms
97ms
128.5ms
36ms
88ms
279ms
850
Beauty & Fitness
63ms
70ms
81ms
102ms
129ms
39ms
92ms
418ms
968
Shopping
63ms
71ms
82ms
105ms
135ms
30ms
94ms
423ms
4,334
Sports
63ms
72ms
83ms
108ms
153ms
36ms
98ms
367ms
1,824
Travel & Transportation
63ms
72ms
83ms
107ms
135ms
30ms
95ms
809ms
1,306
Autos & Vehicles
63ms
72ms
84ms
108ms
138ms
33ms
94ms
334ms
1,059
News
64ms
72ms
88ms
117ms
159ms
30ms
102ms
460ms
6,220
Games
63ms
75ms
90ms
114ms
147ms
33ms
100ms
436ms
2,278
Business & Industrial
65ms
75ms
93ms
122ms
176ms
31ms
109ms
912ms
2,494
Finance
66ms
75ms
94ms
128ms
174ms
36ms
110ms
425ms
2,154
All ☼
65ms
75ms
95ms
126ms
174ms
30ms
109ms
1295ms
40,946
Books & Literature
65ms
75ms
99ms
125ms
153ms
41ms
105ms
345ms
1,262
Computers & Electronics
66ms
78ms
99ms
128ms
165ms
30ms
110ms
471ms
2,655
Online Communities
64ms
78ms
102ms
134ms
180ms
30ms
114ms
463ms
2,193
Arts & Entertainment
67ms
79ms
103ms
137ms
198ms
30ms
118ms
571ms
7,943
Internet & Telecom
68ms
80ms
105ms
137ms
186ms
30ms
118ms
1295ms
2,649
Adult Content
67ms
81ms
105ms
132ms
174ms
30ms
114ms
486ms
4,505
Jobs & Education
66ms
78ms
108ms
151ms
203ms
30ms
123ms
838ms
3,908
Law & Government
67ms
80ms
108ms
150ms
198ms
32ms
121ms
544ms
2,216

Next: This is the first iteration of the report. We plan to expand its functionality once more RTT data is available in CrUX. Feel free to contact us via Email or Twitter and suggest your ideas and improvements.