ICMP echo RTT from Sydney, Australia to Seattle, USA: average 161.9 ms, 0% loss, stability and fiber efficiency insights for this trans-Pacific route.

🇦🇺 Sydney, Australia (SYD) → 🇺🇸 Seattle, USA (SEA)

Measurement round: 2026-08-16T04:07:28Z.

During the 2026-08-16T04:07:28Z measurement round, ICMP echo RTT from Sydney, Australia, to Seattle, USA averaged 161.9 ms over 50 samples, with a minimum of 153.84 ms and a maximum of 176.63 ms. Packet loss was 0%.

For the 12,453.7 km great-circle separation, that average is 1.33 times the theoretical fiber-floor delay and corresponds to 75.3% fiber efficiency. The result placed 7th among the 19 outbound routes measured from the Sydney gateway, putting it in the faster portion of the group.

The standard deviation was 5.72 ms and jitter was 3.81 ms, about 3.5% of the average, which sits close to the network's median variability of 3.3%. Zero packet loss and a 22.79 ms difference between best and worst samples indicate a steady trans-Pacific latency profile under the test conditions.

Latency Summary

Metric	Value
RTT	161.9 ms
Jitter	3.81 ms
Packet Loss	0%
Standard Fiber Floor	121.96 ms
Fiber Efficiency	75.3%
Latency Tier	Fair
Source Region	Asia Pacific
Destination Region	North America

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.

Ping series: SYD → SEA

50 ICMP echo samples at 100 ms intervals · round 2026-08-16T04:07:28Z · avg 161.9 ± 0.81 ms (SE)

Sample distribution: box = interquartile range (157.3–165.4 ms), median 160.8 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	155.65
2	100	159.78
3	200	162.82
4	300	168.51
5	400	166.60
6	500	167.69
7	600	164.35
8	700	168.95
9	800	165.33
10	900	174.14
11	1000	165.47
12	1100	162.66
13	1200	157.76
14	1300	158.71
15	1400	161.16
16	1500	163.38
17	1600	159.93
18	1700	156.16
19	1800	158.33
20	1900	159.20
21	2000	156.36
22	2100	155.69
23	2200	161.11
24	2300	161.50
25	2400	171.85
26	2500	175.61
27	2600	173.49
28	2700	161.28
29	2800	163.81
30	2900	157.25
31	3000	159.27
32	3100	158.10
33	3200	157.99
34	3300	156.98
35	3400	163.28
36	3500	156.93
37	3600	156.86
38	3700	158.13
39	3800	165.45
40	3900	176.63
41	4000	166.19
42	4100	168.19
43	4200	160.42
44	4300	156.07
45	4400	154.29
46	4500	153.84
47	4600	155.52
48	4700	157.05
49	4800	157.63
50	4900	161.65

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 for citation guidance.

Download this dataset

Per-route ICMP ping series, released under CC BY 4.0. Uncompressed plain text — no decompression step needed.

CSV JSON YAML Full dataset

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 ( $n_g=1.4679$ )	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×

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 current measurement round (2026-08-16T04:07:28Z) collected 50 ICMP echo samples on this route. Distribution statistics from that round:

Round Statistic	Value
Minimum RTT	153.84 ms
Average RTT	161.9 ms
Maximum RTT	176.63 ms
Standard deviation	5.72 ms
Stdev / average	3.5%

RTT trend

Estimated route stability across the selected time window.

Average: 161.8 ms
Minimum: 160.1 ms
Maximum: 163.4 ms
Average loss: 0.02%

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

Reverse direction

Seattle to Sydney latency and RTT — 161.3 ms

Fastest routes departing Sydney (SYD)

Sydney to Melbourne latency and RTT — 9.8 ms
Sydney to Singapore latency and RTT — 94.5 ms
Sydney to Tokyo latency and RTT — 101.3 ms
Sydney to Taipei latency and RTT — 131.7 ms
Sydney to Hong Kong latency and RTT — 135.7 ms

Fastest routes arriving at Seattle (SEA)

Los Angeles to Seattle latency and RTT — 26.9 ms
New York to Seattle latency and RTT — 58.7 ms
Ashburn to Seattle latency and RTT — 62.3 ms
Miami to Seattle latency and RTT — 81.9 ms
Tokyo to Seattle latency and RTT — 84.8 ms

Same corridor (Asia Pacific → North America)

Tokyo to Los Angeles latency and RTT — 101.2 ms
Taipei to Seattle latency and RTT — 115.8 ms
Hong Kong to Seattle latency and RTT — 131.6 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. Per-pair files are available at /opendata/latency/latest/pairs/syd-sea.pings.{csv,json,yaml}. When citing, include the route, the measurement round timestamp, and the dataset version — for example: "Hats Network latency dataset, Sydney → Seattle round 2026-08-16T04:07:28Z, CC BY 4.0".

Data auto-generated on August 16, 2026. Explore the full interactive latency matrix or browse more city-pair routes.

Sydney, Australia → Seattle, USA RTT