London to Tokyo ping and RTT: 205.4 ms, 2.99 ms jitter, 93.84 ms fiber floor, and 45.7% efficiency across AS203314. Updated 2026-08-09.

🇬🇧 This page compares the published ping and round-trip time (RTT) from London (LON) to 🇯🇵 Tokyo (TYO) with vacuum and optical-fiber physical limits.

As of August 9, 2026, the London → Tokyo route on Hats Network averages 205.4 ms RTT across a 50-sample daily ICMP echo measurement round (source: RETN), 2.19× the theoretical fiber-floor limit of 93.84 ms.

Among the 19 measured routes departing London, this route ranks 17th fastest by average RTT.

With a stdev-to-average ratio of 1.8%, this route is more stable than the network median of 3.4%. Across the round, per-probe RTT ranged from 201.5 ms to 220.94 ms with a standard deviation of 3.79 ms.

Latency Summary

Metric	Value
RTT	205.4 ms
Jitter	2.99 ms
Packet Loss	0%
Standard Fiber Floor	93.84 ms
Fiber Efficiency	45.7%
Latency Tier	Fair
Source Region	Europe
Destination Region	Asia Pacific

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: LON → TYO

50 ICMP echo samples at 100 ms intervals · round 2026-08-09 · avg 205.4 ± 0.54 ms (SE)

Sample distribution: box = interquartile range (202.6–206.7 ms), median 204.7 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 (93.8 ms) for this route.

Full 50-sample dataset

Seq	Offset (ms)	RTT (ms)
1	0	202.12
2	100	210.68
3	200	205.44
4	300	209.71
5	400	208.96
6	500	211.59
7	600	205.99
8	700	204.41
9	800	202.50
10	900	205.03
11	1000	205.32
12	1100	207.82
13	1200	206.46
14	1300	205.22
15	1400	203.20
16	1500	203.91
17	1600	205.81
18	1700	202.49
19	1800	203.06
20	1900	203.35
21	2000	201.88
22	2100	215.47
23	2200	207.42
24	2300	203.05
25	2400	206.16
26	2500	211.09
27	2600	205.04
28	2700	203.06
29	2800	201.55
30	2900	206.78
31	3000	202.84
32	3100	201.50
33	3200	203.08
34	3300	202.13
35	3400	206.03
36	3500	205.75
37	3600	204.03
38	3700	203.04
39	3800	202.81
40	3900	202.34
41	4000	202.39
42	4100	201.55
43	4200	202.01
44	4300	201.92
45	4400	202.24
46	4500	206.09
47	4600	207.10
48	4700	209.83
49	4800	220.94
50	4900	207.81

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 London (51.50853, -0.12574) and Tokyo (35.68950, 139.69171). It does not disclose either facility address.

Physical Reference	Value
WGS-84 geodesic distance	9,582.1 km
Vacuum RTT floor	63.93 ms
Standard fiber RTT floor ( $n_g=1.4679$ )	93.84 ms
Low-latency fiber material floor	93.46 ms
Engineering floor (5% path allowance)	98.54 ms
Research 1.33× mapped-fiber reference	124.8 ms
Estimated unamplified path loss	2012.2 dB
Transparent optical spans / inline amplifiers	126 / 125
Published RTT inflation over fiber floor	2.19×

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 (2026-08-09) collected 50 ICMP echo samples on this route. Distribution statistics from that round:

Round Statistic	Value
Minimum RTT	201.5 ms
Average RTT	205.4 ms
Maximum RTT	220.94 ms
Standard deviation	3.79 ms
Stdev / average	1.8%

RTT trend

Estimated route stability across the selected time window.

Average: 205.6 ms
Minimum: 203.5 ms
Maximum: 207.5 ms
Average loss: 0.01%

Route Context

Departure PoP: London (LON)
Destination PoP: Tokyo (TYO)
Region overview: Europe → Asia Pacific
Corridor overview: Europe to Asia Pacific
Full global matrix: Backbone Latency Matrix
Physical methodology: Theoretical Fiber Latency

Reverse direction

Tokyo to London latency and RTT — 203.2 ms

Fastest routes departing London (LON)

London to Amsterdam latency and RTT — 5.1 ms
London to Paris latency and RTT — 6.4 ms
London to Frankfurt latency and RTT — 12.8 ms
London to Berlin latency and RTT — 16.5 ms
London to Marseille latency and RTT — 18.2 ms

Fastest routes arriving at Tokyo (TYO)

Taipei to Tokyo latency and RTT — 31.2 ms
Hong Kong to Tokyo latency and RTT — 44.9 ms
Singapore to Tokyo latency and RTT — 69.8 ms
Seattle to Tokyo latency and RTT — 84.6 ms
Los Angeles to Tokyo latency and RTT — 100.8 ms

Same corridor (Europe → Asia Pacific)

Moscow to Hong Kong latency and RTT — 122.1 ms
Moscow to Taipei latency and RTT — 133.1 ms
Marseille to Singapore latency and RTT — 137.3 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/lon-tyo.pings.{csv,json,yaml}. When citing, include the route, the measurement round date, and the dataset version — for example: "Hats Network latency dataset, London → Tokyo round 2026-08-09, CC BY 4.0".

Data auto-generated on August 9, 2026. Explore the full interactive latency matrix or browse more city-pair routes.

London to Tokyo Latency, Ping & RTT | AS203314