Sydney to Seattle Latency, Ping & RTT | AS203314
Sydney to Seattle ping and RTT: 161.4 ms, 1.85 ms jitter, 121.96 ms fiber floor, and 75.6% efficiency across AS203314. Updated 2026-07-19.
🇦🇺 This page compares the published ping and round-trip time (RTT) from Sydney (SYD) to 🇺🇸 Seattle (SEA) with vacuum and optical-fiber physical limits.
Latency Summary
| Metric | Value |
|---|---|
| RTT | 161.4 ms |
| Jitter | 1.85 ms |
| Packet Loss | 0% |
| Standard Fiber Floor | 121.96 ms |
| Fiber Efficiency | 75.6% |
| Latency Tier | Fair |
| Source Region | Asia Pacific |
| Destination Region | North America |
Theoretical Fiber Latency
The public physical reference uses the GeoNames city centres for Sydney (-33.86785, 151.20732) and Seattle (47.60621, -122.33207). It does not disclose either facility address.
| Physical Reference | Value |
|---|---|
| WGS-84 geodesic distance | 12,453.7 km |
| Vacuum RTT floor | 83.08 ms |
| Standard fiber RTT floor () | 121.96 ms |
| Low-latency fiber material floor | 121.47 ms |
| Engineering floor (5% path allowance) | 128.07 ms |
| Research 1.33× mapped-fiber reference | 162.2 ms |
| Estimated unamplified path loss | 2615.3 dB |
| Transparent optical spans / inline amplifiers | 164 / 163 |
| Published RTT inflation over fiber floor | 1.32× |
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 | 159.6 ms |
| Median RTT (p50) | 161.1 ms |
| 95th percentile RTT (p95) | 163.8 ms |
| Maximum RTT | 165.3 ms |
| Jitter | 1.85 ms |
| Packet loss | 0% |
RTT trend
Estimated route stability across the selected time window.
- Average
- 161.7 ms
- Minimum
- 160.1 ms
- Maximum
- 163.1 ms
- Average loss
- 0.03%
Route Context
- Departure PoP: Sydney (SYD)
- Destination PoP: Seattle (SEA)
- Region overview: Asia Pacific → North America
- Full global matrix: Backbone Latency Matrix
- Physical methodology: Theoretical Fiber Latency
Related City-Pair Routes
- Reverse direction: Seattle to Sydney latency and RTT — 162.7 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.