About TrainSpeedTest.net
A free, browser-based GPS train speedometer built for rail enthusiasts, curious travellers, and anyone who has ever wondered exactly how fast their train is going.
Why We Built This
Every train passenger has had that moment — watching the scenery blur past and wondering just how fast the train is really going. We built TrainSpeedTest.net to answer that question instantly, accurately, and without friction: no app store, no account, no ads blocking the speedometer. Just open a browser tab and know your speed.
What We Provide
A Real-Time GPS Speedometer
Twelve distinct speedometer designs, live speed readings in km/h, mph, m/s or knots, and trip tracking with max speed, average speed, and distance — all running client-side in your browser.
Technical Guides & Reference
Dozens of in-depth articles covering how train speed is measured, how fast different train types travel, and world speed records — written to be genuinely useful, not just SEO filler.
The Technology Behind the Speedometer
TrainSpeedTest.net is built with Next.js, TypeScript, and Tailwind CSS. The speed engine reads your device's GPS via the browser's Geolocation API, calculates distance between readings using the Haversine formula, and applies exponential moving average smoothing to filter out GPS noise — producing a stable, accurate speed reading in real time.
Haversine Formula
Calculates great-circle distance between consecutive GPS points, accounting for Earth's curvature.
EMA Smoothing
Filters noisy GPS samples so the displayed speed doesn't jump erratically.
Client-Side Only
All processing happens in your browser. Nothing is uploaded to a server.
Privacy & Accuracy, By Design
We designed TrainSpeedTest.net around two commitments: your location data stays on your device, and every guide we publish is fact-checked against real published specifications for train speeds and technology.
Privacy by Default
Your GPS coordinates are processed locally in your browser and never transmitted to our servers. Trip history lives only in your device's localStorage — delete it anytime.
Built for Everyone
No account, no paywall, no app download. TrainSpeedTest.net works on any modern smartphone, tablet, or desktop browser with GPS support.
Important Limitations
TrainSpeedTest.net is an independent tool and is not affiliated with any railway operator. Speed readings are estimates based on consumer GPS data — not official railway telemetry. Do not use TrainSpeedTest.net for safety-critical decisions. See our full disclaimer for details.
Ready to See How Fast Your Train Is Going?
Open the free GPS speed test on your phone next time you board a train.
No app, no signup, always free.