# Tokyo, Japan → Hong Kong RTT

🇯🇵 **Tokyo, Japan (TYO)** → 🇭🇰 **Hong Kong (HKG)**

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

In the 2026-08-16T04:07:28Z measurement round, the Tokyo-to-Hong Kong path averaged 44.8 ms over 50 ICMP probes, with a minimum of 43.35 ms and a maximum of 48.43 ms. All probes returned replies, and jitter was just 0.97 ms, with a 1.13 ms standard deviation.

The great-circle distance is 2,883.5 km, giving a vacuum RTT floor of 19.24 ms and a theoretical fiber RTT floor of 28.24 ms. The measured average is 1.59 times that fiber floor, so the fiber-efficiency figure is 63 percent; excellent latency does not necessarily mean the path is close to the straight-line fiber minimum.

Within this round's 19-route outbound set, this pair ranked 2nd, placing it among the fastest routes measured. Its standard deviation is about 2.5 percent of the average, below the 3.28 percent median relative variability for the set, and the 0% loss and sub-millisecond jitter reinforce an Excellent latency tier.

## Latency Summary

| Metric               | Value                                                      |
| -------------------- | ---------------------------------------------------------- |
| RTT                  | **44.8 ms**                                                |
| Jitter               | **0.97 ms**                                                |
| Packet Loss          | **0%**                                                     |
| Standard Fiber Floor | **28.24 ms**                                               |
| Fiber Efficiency     | **63%**                                                    |
| Latency Tier         | Excellent                                                  |
| Source Region        | [Asia Pacific](/docs/network/latency/regions/asia-pacific) |
| Destination Region   | [Asia Pacific](/docs/network/latency/regions/asia-pacific) |

## 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 [Tokyo](https://www.geonames.org/1850147) (35.68950, 139.69171) and [Hong Kong](https://www.geonames.org/1819729) (22.27832, 114.17469). It does not disclose either facility address.

| Physical Reference                            | Value          |
| --------------------------------------------- | -------------- |
| WGS-84 geodesic distance                      | **2,883.5 km** |
| Vacuum RTT floor                              | **19.24 ms**   |
| Standard fiber RTT floor ($n_g=1.4679$)       | **28.24 ms**   |
| Low-latency fiber material floor              | **28.12 ms**   |
| Engineering floor (5% path allowance)         | **29.65 ms**   |
| Research 1.33× mapped-fiber reference         | **37.56 ms**   |
| Estimated unamplified path loss               | **605.5 dB**   |
| Transparent optical spans / inline amplifiers | **38 / 37**    |
| Published RTT inflation over fiber floor      | **1.59×**      |

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        | **43.35 ms** |
| Average RTT        | **44.8 ms**  |
| Maximum RTT        | **48.43 ms** |
| Standard deviation | **1.13 ms**  |
| Stdev / average    | **2.5%**     |

## Route Context

* Departure PoP: [Tokyo (TYO)](/docs/network/latency/tyo-tokyo)
* Destination PoP: [Hong Kong (HKG)](/docs/network/latency/hkg-hong-kong)
* Region overview: [Asia Pacific](/docs/network/latency/regions/asia-pacific) → [Asia Pacific](/docs/network/latency/regions/asia-pacific)
* 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**

* [Hong Kong to Tokyo latency and RTT](/docs/network/latency/pairs/hkg-tyo-rtt) — 44.9 ms

**Fastest routes departing Tokyo (TYO)**

* [Tokyo to Taipei latency and RTT](/docs/network/latency/pairs/tyo-tpe-rtt) — 32.3 ms
* [Tokyo to Singapore latency and RTT](/docs/network/latency/pairs/tyo-sin-rtt) — 69.4 ms
* [Tokyo to Seattle latency and RTT](/docs/network/latency/pairs/tyo-sea-rtt) — 84.8 ms
* [Tokyo to Los Angeles latency and RTT](/docs/network/latency/pairs/tyo-lax-rtt) — 101.2 ms
* [Tokyo to Sydney latency and RTT](/docs/network/latency/pairs/tyo-syd-rtt) — 101.9 ms

**Fastest routes arriving at Hong Kong (HKG)**

* [Taipei to Hong Kong latency and RTT](/docs/network/latency/pairs/tpe-hkg-rtt) — 15.5 ms
* [Singapore to Hong Kong latency and RTT](/docs/network/latency/pairs/sin-hkg-rtt) — 30.8 ms
* [Moscow to Hong Kong latency and RTT](/docs/network/latency/pairs/mow-hkg-rtt) — 118.6 ms
* [Seattle to Hong Kong latency and RTT](/docs/network/latency/pairs/sea-hkg-rtt) — 130.4 ms
* [Sydney to Hong Kong latency and RTT](/docs/network/latency/pairs/syd-hkg-rtt) — 135.7 ms

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

* [Melbourne to Sydney latency and RTT](/docs/network/latency/pairs/mel-syd-rtt) — 9.8 ms
* [Sydney to Melbourne latency and RTT](/docs/network/latency/pairs/syd-mel-rtt) — 9.8 ms
* [Hong Kong to Taipei latency and RTT](/docs/network/latency/pairs/hkg-tpe-rtt) — 14.7 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/tyo-hkg.pings.{csv,json,yaml}`. When citing, include the route, the measurement round timestamp, and the dataset version — for example: "Hats Network latency dataset, Tokyo → Hong Kong 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).*

---

## License and attribution

- **Canonical source:** [View the human-readable HTML page](https://hatsnet.io/docs/network/latency/pairs/tyo-hkg-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.