# Ashburn to Johannesburg Latency, Ping & RTT | AS203314

🇺🇸 This page compares the published **ping and round-trip time (RTT)** from **Ashburn (IAD)** to 🇿🇦 **Johannesburg (JNB)** with vacuum and optical-fiber physical limits.

As of August 10, 2026, the Ashburn → Johannesburg route on Hats Network averages 228.3 ms RTT across a 50-sample daily ICMP echo measurement round, 1.78× the theoretical fiber-floor limit of 128.11 ms.

Among the 19 measured routes departing Ashburn, this route ranks 19th fastest by average RTT.

With a stdev-to-average ratio of 2.2%, this route is more stable than the network median of 3.1%. Across the round, per-probe RTT ranged from 223.49 ms to 249.1 ms with a standard deviation of 4.95 ms.

## Latency Summary

| Metric               | Value                                                        |
| -------------------- | ------------------------------------------------------------ |
| RTT                  | **228.3 ms**                                                 |
| Jitter               | **3.51 ms**                                                  |
| Packet Loss          | **0%**                                                       |
| Standard Fiber Floor | **128.11 ms**                                                |
| Fiber Efficiency     | **56.1%**                                                    |
| Latency Tier         | Fair                                                         |
| Source Region        | [North America](/docs/network/latency/regions/north-america) |
| Destination Region   | [Africa](/docs/network/latency/regions/africa)               |

## 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 [Ashburn](https://www.geonames.org/4744870) (39.04372, -77.48749) and [Johannesburg](https://www.geonames.org/993800) (-26.20227, 28.04363). It does not disclose either facility address.

| Physical Reference                            | Value         |
| --------------------------------------------- | ------------- |
| WGS-84 geodesic distance                      | **13,082 km** |
| Vacuum RTT floor                              | **87.27 ms**  |
| Standard fiber RTT floor ($n_g=1.4679$)       | **128.11 ms** |
| Low-latency fiber material floor              | **127.59 ms** |
| Engineering floor (5% path allowance)         | **134.53 ms** |
| Research 1.33× mapped-fiber reference         | **170.38 ms** |
| Estimated unamplified path loss               | **2747.2 dB** |
| Transparent optical spans / inline amplifiers | **172 / 171** |
| Published RTT inflation over fiber floor      | **1.78×**     |

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 (2026-08-10) collected 50 ICMP echo samples on this route. Distribution statistics from that round:

| Round Statistic    | Value         |
| ------------------ | ------------- |
| Minimum RTT        | **223.49 ms** |
| Average RTT        | **228.3 ms**  |
| Maximum RTT        | **249.1 ms**  |
| Standard deviation | **4.95 ms**   |
| Stdev / average    | **2.2%**      |

## Route Context

* Departure PoP: [Ashburn (IAD)](/docs/network/latency/iad-ashburn)
* Destination PoP: [Johannesburg (JNB)](/docs/network/latency/jnb-johannesburg)
* Region overview: [North America](/docs/network/latency/regions/north-america) → [Africa](/docs/network/latency/regions/africa)
* 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**

* [Johannesburg to Ashburn latency and RTT](/docs/network/latency/pairs/jnb-iad-rtt) — 228.5 ms

**Fastest routes departing Ashburn (IAD)**

* [Ashburn to New York latency and RTT](/docs/network/latency/pairs/iad-nyc-rtt) — 6.1 ms
* [Ashburn to Miami latency and RTT](/docs/network/latency/pairs/iad-mia-rtt) — 28.3 ms
* [Ashburn to Los Angeles latency and RTT](/docs/network/latency/pairs/iad-lax-rtt) — 59.1 ms
* [Ashburn to Seattle latency and RTT](/docs/network/latency/pairs/iad-sea-rtt) — 61.3 ms
* [Ashburn to London latency and RTT](/docs/network/latency/pairs/iad-lon-rtt) — 70.3 ms

**Fastest routes arriving at Johannesburg (JNB)**

* [Amsterdam to Johannesburg latency and RTT](/docs/network/latency/pairs/ams-jnb-rtt) — 171.9 ms
* [Berlin to Johannesburg latency and RTT](/docs/network/latency/pairs/ber-jnb-rtt) — 172.1 ms
* [London to Johannesburg latency and RTT](/docs/network/latency/pairs/lon-jnb-rtt) — 179.8 ms
* [Paris to Johannesburg latency and RTT](/docs/network/latency/pairs/par-jnb-rtt) — 180.9 ms
* [Frankfurt to Johannesburg latency and RTT](/docs/network/latency/pairs/fra-jnb-rtt) — 188.9 ms

**Same corridor (North America → Africa)**

* [New York to Johannesburg latency and RTT](/docs/network/latency/pairs/nyc-jnb-rtt) — 221.8 ms
* [Miami to Johannesburg latency and RTT](/docs/network/latency/pairs/mia-jnb-rtt) — 259.4 ms
* [Seattle to Johannesburg latency and RTT](/docs/network/latency/pairs/sea-jnb-rtt) — 282.7 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/iad-jnb.pings.{csv,json,yaml}`. When citing, include the route, the measurement round date, and the dataset version — for example: "Hats Network latency dataset, Ashburn → Johannesburg round 2026-08-10, CC BY 4.0".

***

*Data auto-generated on August 10, 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/iad-jnb-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.