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 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 August 2024 (excluding empty values, which resulted in 49,812). Here are the median (p50) values by device type:

Mobile
156ms
Desktop
99ms
All Devices
144ms

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:

Mobile
106ms
123ms
156ms
215ms
274ms
33ms
177ms
1607ms
49,077
All Devices
92ms
114ms
144ms
201ms
268ms
27ms
165ms
1605ms
49,812
Desktop
67ms
78ms
99ms
130ms
177ms
21ms
113ms
947ms
40,400

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.

:
All Devices
MobileDesktop
<100ms
100–150ms
150–200ms
200–250ms
>250ms
Rank
Country
p50
1.
Netherlands
69ms
2.
Norway
76ms
3.
Sweden
81ms
4.
Denmark
82ms
5.
Belgium
84ms
6.
Taiwan
87ms
7.
United Kingdom
90ms
8.
Switzerland
90ms
9.
Germany
91ms
10.
Czechia
91ms
...
...
...
61.
Kazakhstan
212ms
62.
India
216ms
63.
Egypt
217ms
64.
South Africa
240ms
65.
Venezuela
246ms
66.
Kenya
259ms
67.
Sri Lanka
280ms
68.
Iran
300ms
69.
Pakistan
312ms
70.
Nigeria
342ms

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:

:
All Devices
MobileDesktop
Adult Content
104ms
130ms
172ms
244ms
311ms
27ms
194ms
898ms
6,716
Arts & Entertainment
99ms
119ms
158ms
220ms
281ms
39ms
178ms
895ms
10,316
Jobs & Education
85ms
114ms
155ms
213ms
272.5ms
39ms
170ms
857ms
3,870
Books & Literature
98ms
116ms
153ms
204ms
254ms
55ms
166ms
562ms
1,491
Online Communities
90ms
116ms
152.5ms
214ms
273ms
39ms
171ms
769ms
2,796
Internet & Telecom
93ms
116ms
150ms
207ms
263ms
39ms
169ms
1605ms
3,231
Law & Government
91ms
113ms
147.5ms
210ms
261ms
39ms
166ms
660ms
2,184
All ☼
92ms
114ms
144ms
201ms
268ms
27ms
165ms
1605ms
49,812
Finance
87ms
105ms
143ms
195ms
257ms
39ms
160ms
876ms
2,425
Computers & Electronics
87ms
111ms
140ms
192ms
254ms
42ms
159ms
1054ms
2,978
Games
88ms
107ms
139ms
187ms
255ms
39ms
157ms
725ms
3,049
News
93ms
114ms
138ms
186ms
248ms
48ms
158ms
977ms
7,802
Business & Industrial
87ms
106ms
136ms
183ms
249ms
36ms
155ms
1168ms
2,785
Sports
92ms
111ms
135ms
174ms
248ms
55ms
153ms
743ms
2,301
Travel & Transportation
92ms
109ms
128ms
157ms
212ms
55ms
143ms
790ms
1,537
Autos & Vehicles
90ms
107ms
124ms
159ms
212ms
45ms
141ms
807ms
1,245
Food & Drink
88ms
105ms
121ms
153ms
224ms
54ms
140ms
434ms
1,017
Beauty & Fitness
87ms
102ms
120ms
150ms
199ms
52ms
136ms
660ms
1,034
Shopping
85ms
100ms
119ms
151ms
204ms
38ms
135ms
626ms
4,660

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.