About MPH Tester
A free browser-based GPS speedometer built for accuracy and simplicity.
What is MPH Tester?
MPH Tester is a free online GPS speedometer that runs entirely in your web browser. No app download, no account creation, no subscription fees. Just open the website and start measuring your speed.
We built this tool because we noticed that most speedometer apps are bloated with ads, require unnecessary permissions, or force you to create an account just to check your speed. MPH Tester is different. It does one thing and does it well.
How It Works
MPH Tester uses the Geolocation API built into your browser to access GPS data from your device. When you click "Start Test", your browser requests permission to access location services. Once granted, we read your position updates and calculate speed from the GPS velocity data.
- No installation required - runs in any modern browser
- Works offline - after the initial page load, GPS functions without internet
- No data stored - your location never leaves your device
- Cross-platform - works on iPhone, Android, tablets, and laptops with GPS
Why We Built This
The idea came from a simple frustration: wanting to check if a car's dashboard speedometer was accurate without downloading yet another app.
We realized that GPS speed measurement doesn't need a native app. The browser already has access to location data. So we built a clean, fast, no-nonsense speedometer that anyone can use instantly.
Since then, we've expanded to support different vehicle types with tailored interfaces for cars, bikes, trains, boats, scooters, aircraft, and more.
Accuracy
GPS speed measurement is highly accurate at moderate to high speeds. At speeds above 20 km/h, expect accuracy within 0.5-2 km/h depending on your device's GPS chipset and satellite visibility.
Low-speed measurements (walking pace) are less reliable due to GPS position jitter. For best results:
- Use outdoors with clear sky visibility
- Wait for a stable GPS lock before starting
- Modern phones (iPhone 12+, Samsung Galaxy S21+) have better GPS accuracy
Vehicle Speed Tests
We offer specialized speed tests for different vehicles:
Privacy Commitment
Your privacy matters. MPH Tester processes all GPS data locally on your device. We never transmit, store, or log your location data on our servers. Period.
We use basic analytics (Google Analytics) to understand traffic patterns and improve the site, but no personally identifiable location data is ever collected.
Read our full Privacy Policy for details.
Contact Us
Have questions, feedback, or feature requests? We'd love to hear from you.
Or visit our Contact Page for more ways to reach us.