Sydney to London Latency, Ping & RTT | AS203314
Sydney to London ping and RTT: 246.4 ms, 1.34 ms jitter, 166.37 ms fiber floor, and 67.5% efficiency across AS203314. Updated 2026-07-19.
🇦🇺 This page compares the published ping and round-trip time (RTT) from Sydney (SYD) to 🇬🇧 London (LON) with vacuum and optical-fiber physical limits.
Latency Summary
| Metric | Value |
|---|---|
| RTT | 246.4 ms |
| Jitter | 1.34 ms |
| Packet Loss | 0% |
| Standard Fiber Floor | 166.37 ms |
| Fiber Efficiency | 67.5% |
| Latency Tier | Fair |
| Source Region | Asia Pacific |
| Destination Region | Europe |
Theoretical Fiber Latency
The public physical reference uses the GeoNames city centres for Sydney (-33.86785, 151.20732) and London (51.50853, -0.12574). It does not disclose either facility address.
| Physical Reference | Value |
|---|---|
| WGS-84 geodesic distance | 16,988.9 km |
| Vacuum RTT floor | 113.34 ms |
| Standard fiber RTT floor () | 166.37 ms |
| Low-latency fiber material floor | 165.7 ms |
| Engineering floor (5% path allowance) | 174.71 ms |
| Research 1.33× mapped-fiber reference | 221.27 ms |
| Estimated unamplified path loss | 3567.7 dB |
| Transparent optical spans / inline amplifiers | 223 / 222 |
| Published RTT inflation over fiber floor | 1.48× |
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 | 244.7 ms |
| Median RTT (p50) | 246.2 ms |
| 95th percentile RTT (p95) | 248.1 ms |
| Maximum RTT | 249.5 ms |
| Jitter | 1.34 ms |
| Packet loss | 0% |
RTT trend
Estimated route stability across the selected time window.
- Average
- 246.5 ms
- Minimum
- 244.5 ms
- Maximum
- 248.9 ms
- Average loss
- 0.02%
Route Context
- Departure PoP: Sydney (SYD)
- Destination PoP: London (LON)
- Region overview: Asia Pacific → Europe
- Full global matrix: Backbone Latency Matrix
- Physical methodology: Theoretical Fiber Latency
Related City-Pair Routes
- Reverse direction: London to Sydney latency and RTT — 243.5 ms
- Sydney to Melbourne latency and RTT — 9.8 ms
- Sydney to Singapore latency and RTT — 94.7 ms
- Sydney to Tokyo latency and RTT — 101.8 ms
- Sydney to Hong Kong latency and RTT — 124.7 ms
- Sydney to Taipei latency and RTT — 133.7 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.