Tools
Speed tools
30 free speed tools in one place. A live GPS speedometer, unit converters, automotive and running calculators, all running in your browser with nothing to install.
Live speedometer & vehicle pages
Read your real GPS speed in the browser, with guides tuned to each vehicle.
- GPS Speedometer The live speedometer. Real-time GPS speed in MPH or KPH, no install.
- Motorcycle speedometer Live GPS speed plus why bike dashes over-read 5 to 10 percent.
- Bicycle speedometer GPS speed with no wheel magnet or circumference calibration.
- Boat speedometer Speed Over Ground for boats, kayaks, and jet skis.
- Car speed test Check your car speedometer accuracy against GPS in 10 minutes.
- Train speed test Measure train speed through the window with phone GPS.
Speed unit converters
Convert between every common speed unit, live.
- Speed converter (all units) mph, km/h, knots, m/s, fps, and Mach in one live tool.
- MPH to KPH Miles per hour to kilometers per hour, with table.
- KPH to MPH Kilometers per hour to miles per hour, with table.
- Knots to MPH Nautical miles per hour to mph.
- Knots to KPH Nautical miles per hour to km/h.
- m/s to MPH Meters per second to miles per hour.
- m/s to KPH Meters per second to kilometers per hour.
- Wind speed converter mph, km/h, knots, m/s, and the Beaufort scale.
- Running pace converter min/km, min/mile, mph, and kph, all linked.
Automotive calculators
Acceleration, drag racing, gearing, tires, fuel, and braking.
- 0-60 mph calculator Acceleration time, g-force, and 0-100 km/h equivalent.
- Quarter mile calculator 1/4 mile ET and trap speed from weight and horsepower.
- Gear ratio calculator Road speed from RPM, tire size, gear, and final drive.
- Tire size calculator Speedometer error from a tire or wheel change.
- MPG calculator Fuel economy across MPG, L/100km, km/L, plus trip cost.
- Stopping distance calculator Reaction plus braking distance by speed and surface.
Running & fitness
Pace, race prediction, heart rate, and calories.
- Marathon pace calculator Required pace and splits for any race distance.
- Race time predictor Predict 5K, 10K, half, and marathon from one result.
- Multipoint pace calculator Segment splits and average pace across checkpoints.
- Heart rate zones calculator 5 training zones in bpm from your age.
- Calories burned running MET-based kcal from weight, distance, and pace.
- Calories burned cycling MET-based kcal with road grade adjustment.
Physics & general
The everyday speed, distance, and time math.
Guides & reference
The background reading behind the tools.