Network Latency Test Measure Latency to Any Server From Around the World
Measure the network latency between locations around the world and your server. Enter a host name or IP address and get the round-trip time and packet loss from each location, then learn what latency is, what causes it and how to reduce it.
At a glance
- Free latency test: sends 5 ICMP echo requests from each location to your host and reports the average round-trip time and packet loss.
- Several locations at once: compare latency from up to 3 locations side by side without an account.
- Find where delay starts: the Traceroute Test shows the latency to every hop on the path.
- Rule of thumb: light in fiber covers about 200 km per millisecond, so every 1,000 km of distance adds at least 10 ms of round-trip time.
- Note: this tests latency to your server from our locations, not the latency of your own internet connection.
How to test network latency
- Enter your server's host name (such as
www.example.com) or IPv4 address above and click Test latency. - The Ping Test opens with your host. Select up to three locations, for example one near the server and two near your users, and run it.
- Compare the average latency and packet loss between locations. For a hop-by-hop view, run the Traceroute Test from the slowest location.
What is network latency?
Network latency is the time it takes for data to travel from one point on a network to another. It is usually measured as round-trip time (RTT): the time for a small packet to reach the destination and for the reply to come back, in milliseconds. Latency is different from bandwidth: bandwidth is how much data can be sent per second, latency is how long each piece of data takes to arrive. A connection can have high bandwidth and still feel slow if its latency is high, because every request has to wait for the round trip.
What causes network latency?
- Distance (propagation delay): signals in fiber travel at about two-thirds of the speed of light, roughly 200 km per millisecond.
- Routing: traffic rarely takes a straight line; each router hop and indirect route adds delay.
- Congestion and queuing: busy links and routers hold packets in queues.
- Transmission medium: fiber, copper, cellular and satellite links add different delays; geostationary satellite links add about 500 ms or more.
- Server processing: a slow or overloaded server delays its replies.
Typical latency by distance
| Path | Typical round-trip time |
|---|---|
| Same city or data center region | 1–10 ms |
| Same country or region | 10–40 ms |
| Across North America or Europe | 30–90 ms |
| Transatlantic (US East to Western Europe) | 70–100 ms |
| Transpacific (US West to East Asia) | 100–180 ms |
| Opposite sides of the world | 200–300 ms |
Real values depend on routes and network conditions; measure your own paths to know them.
What is a good network latency?
For websites and APIs, under 50 ms to the nearest users is excellent and under 100 ms is good. Video calls start to suffer above about 150 ms, and online games above 50 to 100 ms. Packet loss matters as much as latency: even 1–2% loss causes retransmissions and visible slowdowns.
How to reduce network latency
- Serve content closer to users: use a CDN, edge caching or servers in the regions where your users are.
- Reduce round trips: enable HTTP keep-alive, HTTP/2 or HTTP/3, TLS 1.3 and session resumption, and combine or cache requests.
- Choose better routes: good hosting and transit providers, and anycast DNS.
- Fix congestion: check the traceroute for the hop where latency jumps and work with the network that owns it.
Related free tools
- Ping Test: latency and packet loss from multiple locations.
- Traceroute Test: latency and loss at every hop.
- Website Speed Test: how latency affects the full page load, request by request.
- Web Server Test: DNS, connect, TLS and time to first byte for a URL.
To track latency to your servers 24/7 with alerts, see Dotcom-Monitor.
Frequently asked questions
What is network latency?
Network latency is the time data takes to travel across a network, usually measured as the round-trip time of a small packet in milliseconds. Lower latency means faster responses.
How do I test network latency to a server?
Ping the server from several locations. This page's latency test opens the Dotcom-Tools Ping Test, which sends five ICMP packets from each location and reports the average round-trip time and packet loss.
What is a good latency?
Under 50 ms is excellent and under 100 ms is good for websites and APIs. Above 150 ms, video calls and other real-time applications start to suffer.
What is the difference between latency and bandwidth?
Bandwidth is how much data a connection can carry per second; latency is how long each piece of data takes to arrive. Web pages make many small requests, so they are often limited more by latency than by bandwidth.
Does this test my own internet latency?
No. It measures latency from Dotcom-Tools' test locations to the server you enter. To test your own connection, use an internet speed test from your device.
Why is latency high from one location only?
Usually because of distance or a poor route between that region and your server. Run the Traceroute Test from that location to see the hop where the latency increases.
What is the difference between latency and ping?
Ping is the tool and the measurement: it sends ICMP echo requests and reports the round-trip time. That round-trip time is the network latency between the two points.
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