Seattle, USA → Sydney, Australia RTT
Explore Seattle, USA to Sydney, Australia ICMP RTT, jitter, packet loss and fiber latency limits on the AS203314 network.
🇺🇸 Seattle, USA (SEA) → 🇦🇺 Sydney, Australia (SYD)
Measurement round: 2026-10-20T08:46:17Z.
Seattle to Sydney averaged 161.9 ms, with RTTs between 149.89 and 176.74 ms and no measured loss.
Sixteenth place among 19 outbound routes places it among Seattle's slower results. The 6.92 ms standard deviation indicates substantial variation around the average.
Latency Summary
| Metric | Value |
|---|---|
| RTT | 161.9 ms |
| Jitter | 7.28 ms |
| Packet Loss | 0% |
| Standard Fiber Floor | 121.96 ms |
| Fiber Efficiency | 75.3% |
| Latency Tier | Fair |
| Source Region | North America |
| Destination Region | Asia Pacific |
Ping Measurement Series
50 ICMP echo probes were recorded in this round. Individual replies and their distribution are shown below.
Ping series: SEA → SYD
50 ICMP echo samples at 100 ms intervals · round 2026-10-20T08:46:17Z · avg 161.9 ± 0.98 ms (SE)
Sample distribution: box = interquartile range (156.2–165.9 ms), median 161.3 ms · whiskers = min–max · diamond = round average · each dot is one measured sample.
How to read this chart
The shaded band spans the measured minimum to maximum RTT of all samples collected up to that point, and the thin line traces the running average. The final position therefore matches the round statistics exactly. The band only widens when a new extreme sample arrives.
The dashed line is the round average, and the shaded band at the bottom is the theoretical fiber-optic floor (122.0 ms) for this route.
Full 50-sample dataset
| Seq | Offset (ms) | RTT (ms) |
|---|---|---|
| 1 | 0 | 168.25 |
| 2 | 100 | 158.30 |
| 3 | 200 | 153.97 |
| 4 | 300 | 165.89 |
| 5 | 400 | 155.05 |
| 6 | 500 | 151.28 |
| 7 | 600 | 164.98 |
| 8 | 700 | 163.57 |
| 9 | 800 | 176.74 |
| 10 | 900 | 160.83 |
| 11 | 1000 | 155.57 |
| 12 | 1100 | 159.95 |
| 13 | 1200 | 153.21 |
| 14 | 1300 | 152.97 |
| 15 | 1400 | 150.36 |
| 16 | 1500 | 161.90 |
| 17 | 1600 | 173.50 |
| 18 | 1700 | 164.79 |
| 19 | 1800 | 159.00 |
| 20 | 1900 | 174.55 |
| 21 | 2000 | 160.84 |
| 22 | 2100 | 158.61 |
| 23 | 2200 | 170.54 |
| 24 | 2300 | 168.84 |
| 25 | 2400 | 168.99 |
| 26 | 2500 | 166.22 |
| 27 | 2600 | 171.93 |
| 28 | 2700 | 169.84 |
| 29 | 2800 | 159.58 |
| 30 | 2900 | 175.18 |
| 31 | 3000 | 164.05 |
| 32 | 3100 | 165.57 |
| 33 | 3200 | 161.82 |
| 34 | 3300 | 159.32 |
| 35 | 3400 | 154.68 |
| 36 | 3500 | 163.34 |
| 37 | 3600 | 156.35 |
| 38 | 3700 | 165.01 |
| 39 | 3800 | 156.21 |
| 40 | 3900 | 157.33 |
| 41 | 4000 | 161.83 |
| 42 | 4100 | 173.82 |
| 43 | 4200 | 158.28 |
| 44 | 4300 | 165.93 |
| 45 | 4400 | 155.92 |
| 46 | 4500 | 154.70 |
| 47 | 4600 | 164.45 |
| 48 | 4700 | 158.53 |
| 49 | 4800 | 152.74 |
| 50 | 4900 | 149.89 |
Download This Route's Data
Download the probe round as CSV, JSON or YAML under CC BY 4.0. Citation details include the route and round timestamp.
Theoretical Fiber Latency
The propagation model uses public city-centre coordinates from GeoNames: Seattle (47.60621, -122.33207) and Sydney (-33.86785, 151.20732). These are not facility coordinates or a surveyed cable path.
| 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 | 1.33× |
The span count assumes 80 km optical spans. Attenuation is a power-loss term, not a propagation delay. See the model assumptions and equations.
Stability & Trend
Statistics from the same 50 replies. They describe this probe round, not continuous historical monitoring.
| Round Statistic | Value |
|---|---|
| Minimum RTT | 149.89 ms |
| Average RTT | 161.9 ms |
| Maximum RTT | 176.74 ms |
| Standard deviation | 6.92 ms |
| Stdev / average | 4.3% |
Estimated RTT trend
Modeled comparison, not historical probe measurements.
- Average
- 162.0 ms
- Minimum
- 160.5 ms
- Maximum
- 163.5 ms
- Average loss
- 0.01%
Route Context
- Departure PoP: Seattle (SEA)
- Destination PoP: Sydney (SYD)
- Region overview: North America → Asia Pacific
- Corridor overview: North America to Asia Pacific
- Full global matrix: Backbone Latency Matrix
- Physical methodology: Theoretical Fiber Latency
Related City-Pair Routes
Reverse direction
- Sydney to Seattle latency and RTT: 161.5 ms
Fastest routes departing Seattle (SEA)
- Seattle to Los Angeles latency and RTT: 25.9 ms
- Seattle to New York latency and RTT: 59.4 ms
- Seattle to Ashburn latency and RTT: 62.8 ms
- Seattle to Miami latency and RTT: 81.1 ms
- Seattle to Tokyo latency and RTT: 85.2 ms
Fastest routes arriving at Sydney (SYD)
- Melbourne to Sydney latency and RTT: 9.7 ms
- Tokyo to Sydney latency and RTT: 101.2 ms
- Taipei to Sydney latency and RTT: 133.3 ms
- Los Angeles to Sydney latency and RTT: 139.1 ms
- Hong Kong to Sydney latency and RTT: 144.4 ms
Same corridor (North America → Asia Pacific)
- Los Angeles to Tokyo latency and RTT: 101.3 ms
- Seattle to Taipei latency and RTT: 115.2 ms
- Seattle to Hong Kong latency and RTT: 127.6 ms
About This Measurement
These ICMP measurements cover the two backbone endpoints. Access networks, routing policy and load can change an end user's result. A probe round is not an SLA.
The underlying replies are available under CC BY 4.0 in the Hats Network latency dataset. Per-pair files are available at /opendata/latency/latest/pairs/sea-syd.pings.{csv,json,yaml}. Cite the route, round timestamp and dataset version. Example: "Hats Network latency dataset, Seattle → Sydney round 2026-10-20T08:46:17Z, CC BY 4.0".
Round published October 20, 2026. See the full interactive latency matrix or browse more city-pair routes.