Ashburn to London Latency, Ping & RTT | AS203314
Ashburn to London ping and RTT: 71.1 ms, 0.53 ms jitter, 58.1 ms fiber floor, and 81.7% efficiency across AS203314. Updated 2026-07-19.
🇺🇸 This page compares the published ping and round-trip time (RTT) from Ashburn (IAD) to 🇬🇧 London (LON) with vacuum and optical-fiber physical limits.
Latency Summary
| Metric | Value |
|---|---|
| RTT | 71.1 ms |
| Jitter | 0.53 ms |
| Packet Loss | 0% |
| Standard Fiber Floor | 58.1 ms |
| Fiber Efficiency | 81.7% |
| Latency Tier | Excellent |
| Source Region | North America |
| Destination Region | Europe |
Theoretical Fiber Latency
The public physical reference uses the GeoNames city centres for Ashburn (39.04372, -77.48749) and London (51.50853, -0.12574). It does not disclose either facility address.
| Physical Reference | Value |
|---|---|
| WGS-84 geodesic distance | 5,932.8 km |
| Vacuum RTT floor | 39.58 ms |
| Standard fiber RTT floor () | 58.1 ms |
| Low-latency fiber material floor | 57.87 ms |
| Engineering floor (5% path allowance) | 61.01 ms |
| Research 1.33× mapped-fiber reference | 77.27 ms |
| Estimated unamplified path loss | 1245.9 dB |
| Transparent optical spans / inline amplifiers | 78 / 77 |
| Published RTT inflation over fiber floor | 1.22× |
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.
Stability & Trend
The following estimated indicators summarize route stability for the current publication period and are intended for comparative planning rather than SLA evaluation.
| Stability Indicator | Value |
|---|---|
| Minimum RTT | 70.5 ms |
| Median RTT (p50) | 71.1 ms |
| 95th percentile RTT (p95) | 71.8 ms |
| Maximum RTT | 72.2 ms |
| Jitter | 0.53 ms |
| Packet loss | 0% |
RTT trend
Estimated route stability across the selected time window.
- Average
- 71.1 ms
- Minimum
- 70.4 ms
- Maximum
- 71.6 ms
- Average loss
- 0.01%
Route Context
- Departure PoP: Ashburn (IAD)
- Destination PoP: London (LON)
- Region overview: North America → Europe
- Full global matrix: Backbone Latency Matrix
- Physical methodology: Theoretical Fiber Latency
Related City-Pair Routes
- Reverse direction: London to Ashburn latency and RTT — 71.2 ms
- Ashburn to New York latency and RTT — 6 ms
- Ashburn to Miami latency and RTT — 33.5 ms
- Ashburn to Los Angeles latency and RTT — 59.7 ms
- Ashburn to Seattle latency and RTT — 61.8 ms
- Ashburn to Amsterdam latency and RTT — 75.4 ms
About This Measurement
Published RTT reflects best-case backbone path behavior. End-user latency also depends on local access networks, congestion, routing policy, and traffic engineering. Stability indicators are comparative estimates, and none of these values is an SLA.
Data auto-generated on July 19, 2026. Explore the full interactive latency matrix or browse more city-pair routes.