# New York, USA → London, UK RTT

🇺🇸 **New York, USA (NYC)** → 🇬🇧 **London, UK (LON)**

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

During the 2026-08-16T04:07:28Z round, ICMP echo RTT from New York to London averaged 63.5 ms, with a minimum of 61.91 ms and a maximum of 68.19 ms over 50 samples. There was no packet loss, and the 1.32 ms standard deviation with 1.15 ms jitter points to a very consistent transatlantic path.

The average sits 16% above the 54.69 ms fiber-floor estimate for the 5,585 km route, giving a fiber efficiency of 86.1%. In this round the route ranked 5th among 19 outbound routes from New York, and its measured variability was well below the 3.28% median relative variability for that outbound group.

For a crossing of this length, the absence of loss and the low jitter figure make 63.5 ms a reliable ICMP latency baseline, though ICMP RTT alone should not be used to predict application performance.

## Latency Summary

| Metric               | Value                                                        |
| -------------------- | ------------------------------------------------------------ |
| RTT                  | **63.5 ms**                                                  |
| Jitter               | **1.15 ms**                                                  |
| Packet Loss          | **0%**                                                       |
| Standard Fiber Floor | **54.69 ms**                                                 |
| Fiber Efficiency     | **86.1%**                                                    |
| Latency Tier         | Excellent                                                    |
| Source Region        | [North America](/docs/network/latency/regions/north-america) |
| 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 [New York City](https://www.geonames.org/5128581) (40.71427, -74.00597) 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                      | **5,585.2 km** |
| Vacuum RTT floor                              | **37.26 ms**   |
| Standard fiber RTT floor ($n_g=1.4679$)       | **54.69 ms**   |
| Low-latency fiber material floor              | **54.48 ms**   |
| Engineering floor (5% path allowance)         | **57.44 ms**   |
| Research 1.33× mapped-fiber reference         | **72.74 ms**   |
| Estimated unamplified path loss               | **1172.9 dB**  |
| Transparent optical spans / inline amplifiers | **74 / 73**    |
| Published RTT inflation over fiber floor      | **1.16×**      |

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        | **61.91 ms** |
| Average RTT        | **63.5 ms**  |
| Maximum RTT        | **68.19 ms** |
| Standard deviation | **1.32 ms**  |
| Stdev / average    | **2.1%**     |

## Route Context

* Departure PoP: [New York (NYC)](/docs/network/latency/nyc-new-york)
* Destination PoP: [London (LON)](/docs/network/latency/lon-london)
* Region overview: [North America](/docs/network/latency/regions/north-america) → [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 New York latency and RTT](/docs/network/latency/pairs/lon-nyc-rtt) — 63.8 ms

**Fastest routes departing New York (NYC)**

* [New York to Ashburn latency and RTT](/docs/network/latency/pairs/nyc-iad-rtt) — 6 ms
* [New York to Miami latency and RTT](/docs/network/latency/pairs/nyc-mia-rtt) — 32.9 ms
* [New York to Seattle latency and RTT](/docs/network/latency/pairs/nyc-sea-rtt) — 58.7 ms
* [New York to Los Angeles latency and RTT](/docs/network/latency/pairs/nyc-lax-rtt) — 58.9 ms
* [New York to Amsterdam latency and RTT](/docs/network/latency/pairs/nyc-ams-rtt) — 68.7 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 (North America → Europe)**

* [New York to Paris latency and RTT](/docs/network/latency/pairs/nyc-par-rtt) — 68.9 ms
* [Ashburn to London latency and RTT](/docs/network/latency/pairs/iad-lon-rtt) — 70.3 ms
* [New York to Frankfurt latency and RTT](/docs/network/latency/pairs/nyc-fra-rtt) — 73.9 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/nyc-lon.pings.{csv,json,yaml}`. When citing, include the route, the measurement round timestamp, and the dataset version — for example: "Hats Network latency dataset, New York → 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).*

---

## License and attribution

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