Paris to London ping and RTT: 6.4 ms, 0.26 ms jitter, 3.37 ms fiber floor, and 52.7% efficiency across AS203314. Updated 2026-08-09.

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

As of August 9, 2026, the Paris → London route on Hats Network averages 6.4 ms RTT across a 50-sample daily ICMP echo measurement round (source: GSL), 1.9× the theoretical fiber-floor limit of 3.37 ms.

Among the 19 measured routes departing Paris, this is the fastest route by average RTT.

With a stdev-to-average ratio of 4.1%, 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 6.06 ms to 7.09 ms with a standard deviation of 0.26 ms.

Latency Summary

Metric	Value
RTT	6.4 ms
Jitter	0.26 ms
Packet Loss	0%
Standard Fiber Floor	3.37 ms
Fiber Efficiency	52.7%
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: PAR → LON

50 ICMP echo samples at 100 ms intervals · round 2026-08-09 · avg 6.4 ± 0.04 ms (SE)

Sample distribution: box = interquartile range (6.2–6.5 ms), median 6.3 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 (3.4 ms) for this route.

Full 50-sample dataset

Seq	Offset (ms)	RTT (ms)
1	0	6.11
2	100	6.10
3	200	6.34
4	300	6.37
5	400	6.61
6	500	6.25
7	600	6.13
8	700	6.12
9	800	6.06
10	900	6.98
11	1000	6.44
12	1100	6.17
13	1200	6.08
14	1300	7.09
15	1400	6.76
16	1500	6.32
17	1600	6.16
18	1700	6.78
19	1800	6.30
20	1900	6.47
21	2000	6.46
22	2100	6.32
23	2200	6.52
24	2300	6.34
25	2400	6.43
26	2500	6.18
27	2600	6.29
28	2700	6.26
29	2800	6.88
30	2900	6.54
31	3000	6.43
32	3100	6.21
33	3200	6.39
34	3300	6.17
35	3400	6.34
36	3500	6.25
37	3600	6.33
38	3700	6.14
39	3800	6.84
40	3900	6.36
41	4000	6.63
42	4100	6.30
43	4200	6.17
44	4300	6.39
45	4400	6.61
46	4500	6.84
47	4600	6.87
48	4700	6.56
49	4800	6.20
50	4900	6.11

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 Paris (48.85341, 2.34880) and London (51.50853, -0.12574). It does not disclose either facility address.

Physical Reference	Value
WGS-84 geodesic distance	344.1 km
Vacuum RTT floor	2.3 ms
Standard fiber RTT floor ( $n_g=1.4679$ )	3.37 ms
Low-latency fiber material floor	3.36 ms
Engineering floor (5% path allowance)	3.54 ms
Research 1.33× mapped-fiber reference	4.48 ms
Estimated unamplified path loss	72.3 dB
Transparent optical spans / inline amplifiers	5 / 4
Published RTT inflation over fiber floor	1.9×

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	6.06 ms
Average RTT	6.4 ms
Maximum RTT	7.09 ms
Standard deviation	0.26 ms
Stdev / average	4.1%

RTT trend

Estimated route stability across the selected time window.

Average: 6.4 ms
Minimum: 6.4 ms
Maximum: 6.5 ms
Average loss: 0.03%

Route Context

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

Reverse direction

London to Paris latency and RTT — 6.4 ms

Fastest routes departing Paris (PAR)

Paris to Amsterdam latency and RTT — 7 ms
Paris to Frankfurt latency and RTT — 7.6 ms
Paris to Marseille latency and RTT — 8.9 ms
Paris to Berlin latency and RTT — 13.9 ms
Paris to Moscow latency and RTT — 43.4 ms

Fastest routes arriving at London (LON)

Amsterdam to London latency and RTT — 5.1 ms
Frankfurt to London latency and RTT — 13.2 ms
Berlin to London latency and RTT — 16.1 ms
Marseille to London latency and RTT — 19 ms
Moscow to London latency and RTT — 43 ms

Same corridor (Europe → Europe)

London to Amsterdam 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/par-lon.pings.{csv,json,yaml}. When citing, include the route, the measurement round date, and the dataset version — for example: "Hats Network latency dataset, Paris → London 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.

Paris to London Latency, Ping & RTT | AS203314