# São Paulo, Brazil → London, UK RTT

🇧🇷 **São Paulo, Brazil (GRU)** → 🇬🇧 **London, UK (LON)**

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

In the 2026-08-16T04:07:28Z round, 50 ICMP echo requests from São Paulo to London recorded an average RTT of 175.8 ms, with a minimum of 170.28 ms and a maximum of 196 ms. Packet loss was 0%, jitter was 3.82 ms, and the standard deviation was 5.34 ms.

The measured average sits 1.9 times above the 92.76 ms fiber floor for the 9,472.8 km great-circle distance, putting the route at 52.8% fiber efficiency and in the “Fair” latency tier. Geographic distance alone cannot explain the delay; the inflation over the fiber floor shows how much of the ideal path remains unrealized.

This route ranks 6th among the 19 outbound São Paulo routes in the round, while the median variability for those 19 paths is 3.28% of average RTT. At about 3.0% of its average, the route’s own standard deviation is slightly below that median, making London a steadier-than-typical transatlantic destination from São Paulo.

## Latency Summary

| Metric               | Value                                                        |
| -------------------- | ------------------------------------------------------------ |
| RTT                  | **175.8 ms**                                                 |
| Jitter               | **3.82 ms**                                                  |
| Packet Loss          | **0%**                                                       |
| Standard Fiber Floor | **92.76 ms**                                                 |
| Fiber Efficiency     | **52.8%**                                                    |
| Latency Tier         | Fair                                                         |
| Source Region        | [South America](/docs/network/latency/regions/south-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 [São Paulo](https://www.geonames.org/3448439) (-23.54750, -46.63611) 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                      | **9,472.8 km** |
| Vacuum RTT floor                              | **63.2 ms**    |
| Standard fiber RTT floor ($n_g=1.4679$)       | **92.76 ms**   |
| Low-latency fiber material floor              | **92.39 ms**   |
| Engineering floor (5% path allowance)         | **97.42 ms**   |
| Research 1.33× mapped-fiber reference         | **123.38 ms**  |
| Estimated unamplified path loss               | **1989.3 dB**  |
| Transparent optical spans / inline amplifiers | **125 / 124**  |
| Published RTT inflation over fiber floor      | **1.9×**       |

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        | **170.28 ms** |
| Average RTT        | **175.8 ms**  |
| Maximum RTT        | **196 ms**    |
| Standard deviation | **5.34 ms**   |
| Stdev / average    | **3.0%**      |

## Route Context

* Departure PoP: [São Paulo (GRU)](/docs/network/latency/gru-sao-paulo)
* Destination PoP: [London (LON)](/docs/network/latency/lon-london)
* Region overview: [South America](/docs/network/latency/regions/south-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 São Paulo latency and RTT](/docs/network/latency/pairs/lon-gru-rtt) — 170.7 ms

**Fastest routes departing São Paulo (GRU)**

* [São Paulo to Miami latency and RTT](/docs/network/latency/pairs/gru-mia-rtt) — 74 ms
* [São Paulo to New York latency and RTT](/docs/network/latency/pairs/gru-nyc-rtt) — 122 ms
* [São Paulo to Ashburn latency and RTT](/docs/network/latency/pairs/gru-iad-rtt) — 128 ms
* [São Paulo to Los Angeles latency and RTT](/docs/network/latency/pairs/gru-lax-rtt) — 130.8 ms
* [São Paulo to Seattle latency and RTT](/docs/network/latency/pairs/gru-sea-rtt) — 155.9 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 (South America → Europe)**

* [São Paulo to Amsterdam latency and RTT](/docs/network/latency/pairs/gru-ams-rtt) — 180 ms
* [São Paulo to Paris latency and RTT](/docs/network/latency/pairs/gru-par-rtt) — 180.2 ms
* [São Paulo to Frankfurt latency and RTT](/docs/network/latency/pairs/gru-fra-rtt) — 186.2 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/gru-lon.pings.{csv,json,yaml}`. When citing, include the route, the measurement round timestamp, and the dataset version — for example: "Hats Network latency dataset, São Paulo → 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/gru-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.