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.
Netherlands
63ms
2.
Norway
74ms
3.
Denmark
79ms
4.
Sweden
80ms
5.
Germany
83ms
6.
Belgium
83ms
7.
Switzerland
83ms
8.
Czechia
85ms
9.
United Kingdom
86ms
10.
Hungary
87ms
...
...
...
61.
Uzbekistan
217ms
62.
Egypt
221ms
63.
Kazakhstan
223ms
64.
Venezuela
238ms
65.
South Africa
246ms
66.
Kenya
265ms
67.
Iran
269ms
68.
Sri Lanka
283ms
69.
Pakistan
301ms
70.
Nigeria
360ms

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:

Beauty & Fitness
85ms
100ms
121ms
150ms
202ms
51ms
135ms
803ms
1,025
Food & Drink
84ms
100ms
121ms
153.5ms
221.5ms
54ms
137ms
440ms
1,000
Shopping
86ms
102ms
124ms
156ms
213ms
49ms
138ms
627ms
4,614
Autos & Vehicles
93ms
108ms
132ms
168ms
213ms
58ms
145ms
541ms
1,198
Travel & Transportation
89ms
107ms
132ms
166ms
218ms
55ms
145ms
819ms
1,442
Sports
89ms
108ms
137ms
184ms
256ms
54ms
156ms
787ms
2,229
News
88ms
105ms
139ms
187ms
252ms
53ms
156ms
1159ms
7,573
Business & Industrial
92ms
114ms
144ms
197ms
255ms
54ms
163ms
1028ms
2,757
Finance
97ms
117ms
148ms
198ms
256ms
60ms
166ms
686ms
2,420
All ☼
95ms
116ms
151ms
209ms
270ms
29ms
171ms
1685ms
48,851
Games
102ms
124ms
153ms
199ms
262ms
53ms
170ms
641ms
3,011
Law & Government
98ms
117ms
155.5ms
204ms
248ms
56ms
166ms
595ms
2,278
Books & Literature
97ms
121ms
157ms
208.5ms
262ms
51ms
170ms
601ms
1,428
Jobs & Education
97ms
122ms
163ms
218ms
268ms
53ms
177ms
875ms
3,964
Computers & Electronics
102ms
127ms
165ms
219ms
270ms
53ms
180ms
1481ms
2,883
Online Communities
101ms
126ms
167ms
228ms
281ms
51ms
183ms
721ms
2,725
Arts & Entertainment
102ms
126ms
168ms
228ms
288ms
53ms
185ms
1195ms
10,192
Internet & Telecom
101ms
125ms
168ms
222ms
276ms
55ms
183ms
1685ms
3,119
Adult Content
104ms
130ms
177.5ms
246ms
307ms
53ms
196ms
1358ms
6,388

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.