Speed, distance, and time are one equation wearing three hats. The Gizmo 421 Speed Calculator solves whichever one you’re missing — leave it to the calculator to figure out your pace, how long the drive takes, or how far the run actually was.
Runners: pick “Speed”, enter your distance and finish time, and the pace line gives you minutes per km and per mile.
Choose what you want to solve for, fill in the other two, and the answer appears live. When you solve for speed you also get the runner’s view of the world — minutes per kilometer and per mile, plus km/h, mph, and m/s equivalents. Unit switches handle miles or kilometers on the distance side, so you can sanity-check a race result or a road trip without doing the 1.609 conversion in your head.
What’s my pace if I ran 5K in 28 minutes? Select Speed, enter 5 km and 28 minutes: about 10.7 km/h, a 9:21 pace per km. How long to drive 250 miles at 70 mph? Select Time, enter the distance and speed — about 3 hours 34 minutes. Does it convert mph to km/h? Yes, speed results come in both plus m/s, and pace in min/km and min/mile. Can it solve for distance? Pick Distance, enter time and speed, and you get how far you traveled.