Speed Distance Time Calculator

Distance = speed × time; rearrange for whichever is missing. The classic check: units must cancel — miles per hour times hours leaves miles. Mixed units (km with mph) are the number-one source of wrong answers.

Trip time runs on average speed, which stops and slowdowns drag well below the cruising number — a '65 mph' highway trip often averages 55 with fuel and rest stops. Pad estimates 10–15% for honesty.