ICMP echo RTT measurements from Sydney, Australia to Seattle, USA: average 161.7 ms, packet loss, jitter, and route statistics for this trans-Pacific path.

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

Measurement round: 2026-08-15T04:03:13Z.

The round 2026-08-15T04:03:13Z measured an average ICMP echo RTT of 161.7 ms from Sydney, Australia to Seattle, USA across 50 samples, with a 152.49 ms minimum, a 186.08 ms maximum, and no packet loss. Against the 12,453.7 km great-circle distance, the theoretical vacuum floor is 83.08 ms and the fiber-optic floor is 121.96 ms, putting the observed mean at 1.33 times the fiber floor and 75.4% fiber efficiency.

Variability was contained: the standard deviation was 7.92 ms and jitter was 7.6 ms, leaving most samples in a roughly 34 ms band. That variability is higher than the 3.08% median standard-deviation-to-average ratio across the 19 routes measured from Sydney in this round, though the route still finished all probes without loss.

Ranked 7th of those 19 routes, Sydney-to-Seattle earned a Fair latency tier. The 152.49–186.08 ms envelope and a 121.96 ms fiber floor indicate that ICMP echo RTT for this Pacific route sits close to the practical lower bound for straight-line fiber optics, with the remaining inflation reflecting the distance involved.

Latency Summary

Metric	Value
RTT	161.7 ms
Jitter	7.6 ms
Packet Loss	0%
Standard Fiber Floor	121.96 ms
Fiber Efficiency	75.4%
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 2026-08-15T04:03:13Z · avg 161.7 ± 1.12 ms (SE)

Sample distribution: box = interquartile range (156.1–164.0 ms), median 159.3 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	153.09
2	100	157.54
3	200	161.64
4	300	158.72
5	400	157.33
6	500	155.85
7	600	154.06
8	700	176.85
9	800	163.62
10	900	157.92
11	1000	166.09
12	1100	157.15
13	1200	155.49
14	1300	156.69
15	1400	159.92
16	1500	154.72
17	1600	181.46
18	1700	186.08
19	1800	166.12
20	1900	162.86
21	2000	168.03
22	2100	157.85
23	2200	153.83
24	2300	163.91
25	2400	160.50
26	2500	154.58
27	2600	180.10
28	2700	163.99
29	2800	157.70
30	2900	154.28
31	3000	152.49
32	3100	157.87
33	3200	160.92
34	3300	162.18
35	3400	158.68
36	3500	170.45
37	3600	160.35
38	3700	155.86
39	3800	153.72
40	3900	154.06
41	4000	164.23
42	4100	161.07
43	4200	155.31
44	4300	171.49
45	4400	158.50
46	4500	163.72
47	4600	162.88
48	4700	181.44
49	4800	165.18
50	4900	156.63

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 (2026-08-15T04:03:13Z) collected 50 ICMP echo samples on this route. Distribution statistics from that round:

Round Statistic	Value
Minimum RTT	152.49 ms
Average RTT	161.7 ms
Maximum RTT	186.08 ms
Standard deviation	7.92 ms
Stdev / average	4.9%

RTT trend

Estimated route stability across the selected time window.

Average: 161.5 ms
Minimum: 159.9 ms
Maximum: 163.3 ms
Average loss: 0.01%

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 — 162.5 ms

Fastest routes departing Sydney (SYD)

Sydney to Melbourne latency and RTT — 9.8 ms
Sydney to Singapore latency and RTT — 94.7 ms
Sydney to Tokyo latency and RTT — 101.6 ms
Sydney to Taipei latency and RTT — 133.2 ms
Sydney to Hong Kong latency and RTT — 135.9 ms

Fastest routes arriving at Seattle (SEA)

Los Angeles to Seattle latency and RTT — 27.5 ms
New York to Seattle latency and RTT — 59 ms
Ashburn to Seattle latency and RTT — 61.3 ms
Miami to Seattle latency and RTT — 82 ms
Tokyo to Seattle latency and RTT — 84.6 ms

Same corridor (Asia Pacific → North America)

Tokyo to Los Angeles latency and RTT — 101.5 ms
Taipei to Seattle latency and RTT — 115.7 ms
Hong Kong to Seattle latency and RTT — 129.9 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 2026-08-15T04:03:13Z, CC BY 4.0".

Data auto-generated on August 15, 2026. Explore the full interactive latency matrix or browse more city-pair routes.

Sydney, Australia → Seattle, USA RTT