Speed Distance Time Calculator
Calculate speed, distance, or time from any two values
Enter two known values to calculate the third. Use any consistent units (e.g., km and hours, or meters and seconds).
How to use
Select what you want to calculate: speed, distance, or time. Enter the two known values and the third is calculated instantly. Use any consistent units (km and hours, miles and hours, meters and seconds, etc.).
Formula
Examples
Road trip distance
Driving at 90 km/h for 3.5 hours covers d = 90 x 3.5 = 315 km.
Finding travel time
A 200 km trip at 80 km/h takes t = 200 / 80 = 2.5 hours (2 hours 30 minutes).
Average speed of a runner
A runner completes a 10 km race in 50 minutes (0.833 hours). Average speed = 10 / 0.833 = 12 km/h.
Frequently asked questions
What is the speed distance time formula?
The formula is d = s x t, where d is distance, s is speed, and t is time. You can rearrange it to solve for any variable: speed = distance / time, and time = distance / speed.
What is the difference between speed and velocity?
Speed is a scalar quantity (magnitude only), while velocity is a vector (magnitude and direction). This calculator works with speed. For example, 60 km/h is a speed, while 60 km/h north is a velocity.
What units should I use?
Any units work as long as they are consistent. If distance is in kilometers and time is in hours, speed will be in km/h. If distance is in meters and time is in seconds, speed will be in m/s. Do not mix units (e.g., miles with hours gives mph, not km/h).
How do I convert between km/h and m/s?
To convert km/h to m/s, divide by 3.6. To convert m/s to km/h, multiply by 3.6. For example, 100 km/h = 27.78 m/s, and 10 m/s = 36 km/h.
Does this formula account for acceleration?
No. The formula d = s x t assumes constant speed (uniform motion). For accelerating objects, you need the kinematic equations: d = v₀t + ½at², where v₀ is initial velocity and a is acceleration.
About this tool
Calculate speed, distance, or time using the formula d = s x t. Enter any two values to solve for the third. Perfect for physics homework and travel planning.
All calculations are performed locally in your browser. Your data never leaves your device.