London to Marseille ping and RTT: 18.2 ms, 0.71 ms jitter, 9.82 ms fiber floor, and 53.9% efficiency across AS203314. Updated 2026-08-09.

🇬🇧 This page compares the published ping and round-trip time (RTT) from London (LON) to 🇫🇷 Marseille (MRS) with vacuum and optical-fiber physical limits.

As of August 9, 2026, the London → Marseille route on Hats Network averages 18.2 ms RTT across a 50-sample daily ICMP echo measurement round (source: GSL), 1.85× the theoretical fiber-floor limit of 9.82 ms.

Among the 19 measured routes departing London, this route ranks 5th fastest by average RTT.

With a stdev-to-average ratio of 4.5%, this route fluctuates more than the network median of 3.4%, so short congestion windows can surface as transient RTT spikes. Across the round, per-probe RTT ranged from 17.22 ms to 20.45 ms with a standard deviation of 0.82 ms.

Latency Summary

Metric	Value
RTT	18.2 ms
Jitter	0.71 ms
Packet Loss	0%
Standard Fiber Floor	9.82 ms
Fiber Efficiency	53.9%
Latency Tier	Ultra-Low
Source Region	Europe
Destination Region	Europe

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 → MRS

50 ICMP echo samples at 100 ms intervals · round 2026-08-09 · avg 18.2 ± 0.12 ms (SE)

Sample distribution: box = interquartile range (17.6–18.7 ms), median 18.0 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 (9.8 ms) for this route.

Full 50-sample dataset

Seq	Offset (ms)	RTT (ms)
1	0	20.45
2	100	18.31
3	200	18.33
4	300	17.59
5	400	17.83
6	500	17.48
7	600	19.01
8	700	17.73
9	800	17.67
10	900	18.11
11	1000	17.73
12	1100	17.45
13	1200	17.40
14	1300	17.53
15	1400	18.44
16	1500	18.74
17	1600	18.28
18	1700	17.44
19	1800	17.61
20	1900	17.95
21	2000	17.38
22	2100	19.68
23	2200	20.30
24	2300	18.95
25	2400	17.77
26	2500	17.53
27	2600	19.35
28	2700	18.78
29	2800	19.31
30	2900	17.97
31	3000	19.21
32	3100	18.25
33	3200	17.57
34	3300	20.14
35	3400	18.81
36	3500	18.38
37	3600	18.11
38	3700	17.75
39	3800	17.30
40	3900	17.22
41	4000	17.54
42	4100	19.26
43	4200	18.13
44	4300	17.62
45	4400	17.33
46	4500	17.29
47	4600	17.64
48	4700	17.81
49	4800	18.05
50	4900	18.49

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 Marseille (43.29695, 5.38107). It does not disclose either facility address.

Physical Reference	Value
WGS-84 geodesic distance	1,002.4 km
Vacuum RTT floor	6.69 ms
Standard fiber RTT floor ( $n_g=1.4679$ )	9.82 ms
Low-latency fiber material floor	9.78 ms
Engineering floor (5% path allowance)	10.31 ms
Research 1.33× mapped-fiber reference	13.06 ms
Estimated unamplified path loss	210.5 dB
Transparent optical spans / inline amplifiers	14 / 13
Published RTT inflation over fiber floor	1.85×

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	17.22 ms
Average RTT	18.2 ms
Maximum RTT	20.45 ms
Standard deviation	0.82 ms
Stdev / average	4.5%

RTT trend

Estimated route stability across the selected time window.

Average: 18.2 ms
Minimum: 18.0 ms
Maximum: 18.4 ms
Average loss: 0.02%

Route Context

Departure PoP: London (LON)
Destination PoP: Marseille (MRS)
Region overview: Europe → Europe
Full global matrix: Backbone Latency Matrix
Physical methodology: Theoretical Fiber Latency

Reverse direction

Marseille to London latency and RTT — 19 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 Moscow latency and RTT — 42.7 ms

Fastest routes arriving at Marseille (MRS)

Paris to Marseille latency and RTT — 8.9 ms
Frankfurt to Marseille latency and RTT — 16.5 ms
Amsterdam to Marseille latency and RTT — 19.8 ms
Berlin to Marseille latency and RTT — 21.6 ms
Moscow to Marseille latency and RTT — 51.3 ms

Same corridor (Europe → Europe)

Amsterdam to London latency and RTT — 5.1 ms
Amsterdam to Frankfurt latency and RTT — 5.9 ms
Frankfurt to Amsterdam latency and RTT — 5.9 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/lon-mrs.pings.{csv,json,yaml}. When citing, include the route, the measurement round date, and the dataset version — for example: "Hats Network latency dataset, London → Marseille 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 Marseille Latency, Ping & RTT | AS203314