Speed Calculator
Calculate Speed by entering distance and time. Get pace per mile or kilometre, projected finish times, and split breakdowns.
Formula
Speed = Distance ÷ Time
Speed equals distance divided by time. Rearrange to find distance (S×T) or time (D÷S). Ensure consistent units.
Worked Examples
Example 1: Road Trip Planning
Problem:How long will it take to drive 450 km at an average speed of 90 km/h?
Solution:Time = Distance ÷ Speed\nTime = 450 km ÷ 90 km/h\nTime = 5 hours\n\nAdd 15-20% for stops and traffic:\nTotal trip time ≈ 5.75-6 hours
Result:5 hours driving (6 hours total)
Example 2: Running Pace
Problem:A runner completes a 10K race in 50 minutes. What was their speed?
Solution:Distance = 10 km\nTime = 50 min = 0.833 hours\n\nSpeed = 10 ÷ 0.833 = 12 km/h\n\nPace = 50 ÷ 10 = 5 min/km\nIn mph: 12 ÷ 1.609 = 7.46 mph
Result:12 km/h (7.46 mph, 5:00/km pace)
Example 3: Flight Distance
Problem:An airplane flies at 850 km/h for 3.5 hours. How far did it travel?
Solution:Distance = Speed × Time\nDistance = 850 km/h × 3.5 h\nDistance = 2,975 km\n\nIn miles: 2,975 ÷ 1.609 = 1,849 miles
Result:2,975 km (1,849 miles)
Frequently Asked Questions
How do I calculate speed from distance and time?
Speed = Distance ÷ Time. For example, if you travel 100 km in 2 hours, your speed is 100 ÷ 2 = 50 km/h. Make sure distance and time units are compatible.
What's the difference between speed and velocity?
Speed is how fast something moves (scalar, just magnitude). Velocity includes direction (vector). A car going 60 mph in circles has constant speed but changing velocity.
How do I calculate average speed?
Average Speed = Total Distance ÷ Total Time. If you drive 100 km in 1 hour, stop for 30 min, then drive 50 km in 1 hour, average speed = 150 km ÷ 2.5 h = 60 km/h.
How does speed affect braking distance?
Braking distance increases with the square of speed. Doubling your speed quadruples braking distance. At 60 mph, stopping distance is about 4× what it is at 30 mph.