# Hong Kong → London, UK RTT

🇭🇰 **Hong Kong (HKG)** → 🇬🇧 **London, UK (LON)**

Measurement round: `2026-08-16T04:07:28Z`.

In the 2026-08-16T04:07:28Z round, 50 ICMP echo probes sent 100 ms apart from Hong Kong to London all came back, producing zero packet loss and an average RTT of 158.7 ms, with a minimum of 154.18 ms and a maximum of 172.16 ms. The standard deviation was 4.34 ms and jitter was 3.3 ms, so the path was relatively stable during the sample.

Against the 9,643.6 km great-circle distance, the round-trip vacuum floor is 64.34 ms and the fiber floor is 94.44 ms. The 158.7 ms average is 1.68 times the fiber floor, which corresponds to 59.5 percent fiber efficiency and leaves a 64.26 ms gap over the straight-line fiber minimum.

This route ranked 12th among the 19 outbound paths measured from Hong Kong in the same round. Its variability ratio of roughly 2.73 percent was below the 3.28 percent median for those paths, meaning the round-trip times clustered more tightly around the average than was typical.

## Latency Summary

| Metric               | Value                                                      |
| -------------------- | ---------------------------------------------------------- |
| RTT                  | **158.7 ms**                                               |
| Jitter               | **3.3 ms**                                                 |
| Packet Loss          | **0%**                                                     |
| Standard Fiber Floor | **94.44 ms**                                               |
| Fiber Efficiency     | **59.5%**                                                  |
| Latency Tier         | Fair                                                       |
| Source Region        | [Asia Pacific](/docs/network/latency/regions/asia-pacific) |
| Destination Region   | [Europe](/docs/network/latency/regions/europe)             |

## Ping Measurement Series

The chart below renders the 50-sample ICMP echo measurement round for this route; an accessible table of every sample is included with the chart.

## Download This Route's Data

This route's measurement round is published as open data (CC BY 4.0) in CSV, JSON, and YAML. See [About This Measurement](#about-this-measurement) for citation guidance.

## Theoretical Fiber Latency

The public physical reference uses the GeoNames city centres for [Hong Kong](https://www.geonames.org/1819729) (22.27832, 114.17469) and [London](https://www.geonames.org/2643743) (51.50853, -0.12574). It does not disclose either facility address.

| Physical Reference                            | Value          |
| --------------------------------------------- | -------------- |
| WGS-84 geodesic distance                      | **9,643.6 km** |
| Vacuum RTT floor                              | **64.34 ms**   |
| Standard fiber RTT floor ($n_g=1.4679$)       | **94.44 ms**   |
| Low-latency fiber material floor              | **94.06 ms**   |
| Engineering floor (5% path allowance)         | **99.17 ms**   |
| Research 1.33× mapped-fiber reference         | **125.6 ms**   |
| Estimated unamplified path loss               | **2025.2 dB**  |
| Transparent optical spans / inline amplifiers | **127 / 126**  |
| Published RTT inflation over fiber floor      | **1.68×**      |

Attenuation is used to estimate the number of 80 km optical spans; it does not directly slow light. See the full [theoretical fiber latency, GeoNames, attenuation, and amplifier methodology](/docs/network/latency/theoretical-fiber-latency).

## Stability & Trend

The current measurement round (2026-08-16T04:07:28Z) collected 50 ICMP echo samples on this route. Distribution statistics from that round:

| Round Statistic    | Value         |
| ------------------ | ------------- |
| Minimum RTT        | **154.18 ms** |
| Average RTT        | **158.7 ms**  |
| Maximum RTT        | **172.16 ms** |
| Standard deviation | **4.34 ms**   |
| Stdev / average    | **2.7%**      |

## Route Context

* Departure PoP: [Hong Kong (HKG)](/docs/network/latency/hkg-hong-kong)
* Destination PoP: [London (LON)](/docs/network/latency/lon-london)
* Region overview: [Asia Pacific](/docs/network/latency/regions/asia-pacific) → [Europe](/docs/network/latency/regions/europe)
* Full global matrix: [Backbone Latency Matrix](/docs/network/latency)
* Physical methodology: [Theoretical Fiber Latency](/docs/network/latency/theoretical-fiber-latency)

## Related City-Pair Routes

**Reverse direction**

* [London to Hong Kong latency and RTT](/docs/network/latency/pairs/lon-hkg-rtt) — 160.6 ms

**Fastest routes departing Hong Kong (HKG)**

* [Hong Kong to Taipei latency and RTT](/docs/network/latency/pairs/hkg-tpe-rtt) — 14.7 ms
* [Hong Kong to Singapore latency and RTT](/docs/network/latency/pairs/hkg-sin-rtt) — 31.5 ms
* [Hong Kong to Tokyo latency and RTT](/docs/network/latency/pairs/hkg-tyo-rtt) — 44.9 ms
* [Hong Kong to Moscow latency and RTT](/docs/network/latency/pairs/hkg-mow-rtt) — 118.2 ms
* [Hong Kong to Seattle latency and RTT](/docs/network/latency/pairs/hkg-sea-rtt) — 131.6 ms

**Fastest routes arriving at London (LON)**

* [Amsterdam to London latency and RTT](/docs/network/latency/pairs/ams-lon-rtt) — 5.2 ms
* [Paris to London latency and RTT](/docs/network/latency/pairs/par-lon-rtt) — 6.4 ms
* [Frankfurt to London latency and RTT](/docs/network/latency/pairs/fra-lon-rtt) — 12.9 ms
* [Berlin to London latency and RTT](/docs/network/latency/pairs/ber-lon-rtt) — 15.2 ms
* [Marseille to London latency and RTT](/docs/network/latency/pairs/mrs-lon-rtt) — 18.9 ms

**Same corridor (Asia Pacific → Europe)**

* [Taipei to Moscow latency and RTT](/docs/network/latency/pairs/tpe-mow-rtt) — 132.7 ms
* [Singapore to Marseille latency and RTT](/docs/network/latency/pairs/sin-mrs-rtt) — 140.6 ms
* [Hong Kong to Berlin latency and RTT](/docs/network/latency/pairs/hkg-ber-rtt) — 145.1 ms

## About This Measurement

Published RTT reflects best-case backbone path behavior measured with ICMP echo probes between PoPs. End-user latency also depends on local access networks, congestion, routing policy, and traffic engineering. None of these values is an SLA.

The measurement round behind this page is published as open data under **CC BY 4.0** in the [Hats Network latency dataset](/opendata/latency/). Per-pair files are available at `/opendata/latency/latest/pairs/hkg-lon.pings.{csv,json,yaml}`. When citing, include the route, the measurement round timestamp, and the dataset version — for example: "Hats Network latency dataset, Hong Kong → London round 2026-08-16T04:07:28Z, CC BY 4.0".

***

*Data auto-generated on August 16, 2026. Explore the [full interactive latency matrix](/docs/network/latency) or browse more [city-pair routes](/docs/network/latency/pairs).*

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## License and attribution

- **Canonical source:** [View the human-readable HTML page](https://hatsnet.io/docs/network/latency/pairs/hkg-lon-rtt).
- **Original documentation:** © Hats Network Inc., licensed under [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/).
- **Public latency data:** © Hats Network Inc., licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).
- **Full terms:** [Content and Data License](https://hatsnet.io/docs/legal/content-and-data-license) — includes attribution requirements, third-party material, trademarks, source code and other exclusions.