Speed, Distance & Time Calculator

1. Speed, Distance & Time Calculation
2. Average Speed formula
3. Distance formula
4. Duration (Time) formula
5. How to calculate the average speed of a car?

    Speed, Distance & Time Calculation

In order to use the above speed, distance & time calculator, or do such math on your own, you will need to know two out of three metrics: speed, distance, time. You will need to convert the metrics to the same time and distance units, e.g. miles, kilometers, meters, yards, feet, and hours, minutes or seconds. For example, if you have speed in mph (miles per hour), time should also be in hours. If you have distance in kilometers, then speed should also be in km/h (kilometers per hour).

The unit of the result will depend on the units you input, but our speed calculator will conveniently display additional units where appropriate.

    Average Speed formula

The formula for average speed, also called average velocity in physics and engineering, is:

v = d / t

where v is the velocity, d is the distance, and t is the time, so you can read it as Speed = Distance / Time. As noted above, make sure you convert the units appropriately first, or use our speed calculator which does that automatically. The resulting unit will depend on the units for both time and distance, so if your input was in miles and hours, the speed will be in mph. If it was in meters and seconds, it will be in m/s (meters per second).

Example: If you took a plane from New York to Los Angeles and the flight was 5 hours of air time, what was the speed of the plane, given that the flight path was 2450 miles? The answer is 2450 / 5 = 490 mph (miles per hour) average speed. If you want the result in km/h, you can convert from miles to km to get 788.58 km/h.

    Distance formula

The formula for distance, if you know time (duration) and the average speed, is:

d = v x t

where v is the velocity (average speed), t is the time and d is distance, so you can read it as Distance = Speed x Time. The result will depend on the unit of the speed metric, for example if speed is given in mph, the result will be in miles, if it is given in km/h, the result will be in kilometers. As usual, make sure that the time unit of the speed measure is the same as the time unit for the duration of the trip. Our distance calculator will sometimes output the distance in more than one unit, for your convenience.

Example: If a truck travelled at an average speed of 80 km per hour for 4 hours, how many miles did it cover in that time? To find the miles covered, first, calculate 80 * 4 = 320 km, then convert km to miles by dividing by 1.6093 or by using our km to miles converter to get the answer: 198.84 miles.

    Duration (Time) formula

The time, or more precisely, the duration of the trip, can be calculated knowing the distance and the average speed using the formula:

t = d / v

where d is the distance travelled, v is the speed (velocity) and t is the time, so you can read it as Time = Distance / Speed. Make sure you convert the units so both their distance and time components match, or use our trip duration calculator above which will handle conversions automatically. For example, if you have distance in miles and speed in km/h, you will need to convert speed to mph or distance to kilometers. The time unit of the result will match the time unit of the speed measure, so if it is measured in something per hour, the result will be in hours. If it is measured in some unit per second, the result will be in seconds.

Example: If a train can travel 500 miles with an average speed of 50 miles per hour, how long it would take it to complete a 500-mile route? To find the answer, use the formula and substitute the values, resulting in 500 / 50 = 10 hours.

    How to calculate the average speed of a car?

Say you travelled a certain distance with a car or another vehicle and you want to calculate what its average speed was. The easiest way to do that would be by using the calculator above, but if you prefer, you can also do the math yourself. Either way, you need to know the distance to a satisfactory approximation, for which you can use a map (e.g. Google Maps) to measure the distance from point to point. Make sure you measure closely to the path you took, and not via a straight line, unless you travelled by air in which case that would be a good approximation. Of course, having a GPS reading of the distance would be more precise. Then you need to know the travel time. Make sure you subtract any rests or stops you made from the total trip duration.

If the total distance travelled was 500 miles and the time it took you was 5 hours, then your average speed was 500 / 5 = 100 miles per hour (mph). If the distance was 300 kilometers and it took you 5 hours to cover it, your speed was 300 / 5 = 60 km/h (kilometers per hour).