Speed Distance Time Calculator

Calculate speed, distance, or time from any two known values

The speed distance time calculator solves the fundamental kinematic equation: Speed = Distance ÷ Time. Enter any two known values to instantly calculate the third. Switch between metric (km/h, m/s) and imperial (mph, ft/s) units as needed — perfect for physics homework, travel planning, and real-world estimates.

Speed Distance Time Calculator

Select what you want to calculate:

Formula Reference

s = d/t
Speed
d = s×t
Distance
t = d/s
Time

How to Use the Speed Distance Time Calculator

The speed distance time calculator solves the core kinematic relationship: Speed = Distance ÷ Time. This single formula connects three variables — knowing any two lets you find the third in one step.

Step 1: Choose What to Calculate

Select "Speed," "Distance," or "Time" from the three options at the top. The calculator will disable the field for that variable (since you're solving for it) and prompt you to fill in the other two.

Step 2: Select Your Unit System

Toggle between Metric and Imperial using the switch in the top-right corner. Metric uses km/h for speed and km for distance. Imperial uses mph for speed and miles for distance. Time is always in hours for consistency — if your time is in minutes, divide by 60 before entering it.

Step 3: Enter the Known Values

Fill in the two known values and click Calculate. For example: if a car travels at 90 km/h for 2.5 hours, enter Speed = 90 and Time = 2.5 to get Distance = 225 km.

Common Use Cases

Travel planning: "If I drive at 65 mph, how long does a 400-mile trip take?" Answer: Time = 400 / 65 = 6.15 hours (about 6 hours 9 minutes).

Physics problems: Calculate the average speed of an object that travels 150 meters in 12 seconds. Speed = 150 m / 12 s = 12.5 m/s.

Running/cycling: If you run a 10km race in 55 minutes (0.917 hours), your average speed = 10 / 0.917 = 10.9 km/h.

Unit Conversion Tips

To convert m/s to km/h, multiply by 3.6. To convert km/h to mph, multiply by 0.6214. The speed distance time calculator handles these conversions automatically when you switch the unit toggle.

Frequently Asked Questions

What is the speed distance time formula?

The fundamental formula is Speed = Distance / Time. You can rearrange it to find any variable: Distance = Speed × Time, or Time = Distance / Speed. This relationship works for any consistent set of units — just make sure speed, distance, and time units are compatible.

How do I convert mph to km/h?

Multiply mph by 1.60934 to get km/h. For example, 60 mph = 60 × 1.60934 = 96.56 km/h. To go from km/h to mph, multiply by 0.62137. This tool handles the conversion automatically when you switch unit modes.

Is this calculator free?

Yes, completely free with no signup required. All calculations happen in your browser — no data is sent to any server.

Is my data private?

Yes. All calculations run locally in your browser. Nothing is transmitted or stored anywhere.

What units does this calculator support?

Metric: meters per second (m/s) and kilometers per hour (km/h) for speed, meters (m) and kilometers (km) for distance, seconds and hours for time. Imperial: feet per second (ft/s) and miles per hour (mph) for speed, feet (ft) and miles (mi) for distance.