Speed Distance Time Calculator

What is a speed distance time calculator?

A speed distance time calculator finds any one of the three quantities when you know the other two. Want to know how fast you drove? Enter the distance and the time. Need to know how far you will get? Enter your speed and the time. Wondering when you will arrive? Enter the distance and your speed. This online speed distance time calculator accepts km, miles, metres and nautical miles, speeds in km/h, mph, m/s and knots, and time in hours, minutes and seconds – and shows the answer with steps, so you can check the working out for homework or exams.

Speed distance time formula

All three formulas come from one equation. Speed equals distance over time:

Speed = Distance ÷ Time  ·  Distance = Speed × Time  ·  Time = Distance ÷ Speed

• Speed (S) – how fast something moves, e.g. km/h, mph or m/s
• Distance (D) – how far it travels, e.g. km, miles or metres
• Time (T) – how long the journey takes, e.g. hours or seconds

The units must match: if speed is in km/h, distance must be in km and time in hours. The calculator converts mixed units for you automatically.

What is the speed distance time triangle?

The speed distance time triangle is a memory aid. Draw a triangle, put D at the top and S and T side by side at the bottom. Cover the quantity you want: covering D leaves S × T; covering S leaves D over T; covering T leaves D over S. It is the quickest way to remember which formula to use in a non-calculator paper.

How to use this calculator

1. Choose what you want to find: speed, distance or time.
2. Enter the two known values and pick their units. Time is split into hours, minutes and seconds, so 2 h 30 min needs no conversion.
3. Optionally choose the units for the answer – for example get a speed in mph from a distance in km.
4. Read the answer, the conversions to other units and the step-by-step solution.

How to calculate speed, distance and time – examples

Example 1: find the speed

A car travels 150 km in 2 hours 30 minutes. First convert the time to hours: 30 min = 0.5 h, so T = 2.5 h. Speed = 150 ÷ 2.5 = 60 km/h (37.28 mph or 16.67 m/s). This is the calculator's default example.

Example 2: find the distance

A cyclist rides at 18 km/h for 1 hour 40 minutes. T = 1 + 40/60 = 1.667 h. Distance = 18 × 1.667 = 30 km.

Example 3: find the time

A train covers 420 km at an average speed of 80 km/h. Time = 420 ÷ 80 = 5.25 h = 5 hours 15 minutes. Multiply the decimal part by 60 to turn hours into minutes: 0.25 × 60 = 15.

Example 4: speed in m/s

A sprinter runs 100 m in 10 seconds. Speed = 100 ÷ 10 = 10 m/s, which is 36 km/h. To convert m/s to km/h multiply by 3.6; to convert km/h to m/s divide by 3.6.

Average speed

Average speed is total distance ÷ total time – not the average of the speeds. If you drive 60 km at 60 km/h (1 hour) and another 60 km at 30 km/h (2 hours), you cover 120 km in 3 hours, so your average speed is 40 km/h, not 45. For an average speed calculation, add up all the distances and all the times first, then divide. For a trip that uses fuel as well as time, the fuel cost calculator estimates the petrol cost for the same distance.

Unit conversions you need

For any other unit, use the unit converter; to add up journey times, use the time calculator.

Speed distance time for running, cycling, driving and boats

• Running and walking: runners think in pace (minutes per km). When you solve for speed, the calculator also shows your pace. A 5 km run in 30 minutes is 10 km/h, or a pace of 6 min/km. Walking speed is about 5 km/h; a treadmill at 8 km/h covers 4 km in 30 minutes.
• Cycling: a leisure rider averages 15–20 km/h; a trained road cyclist 28–35 km/h.
• Driving: use realistic averages, not the speed limit – an Indian highway trip with stops averages 50–65 km/h.
• Marine and aviation: ships and aircraft use nautical miles (nm) and knots. One knot is one nautical mile per hour (1.852 km/h), so a boat at 12 knots covers 36 nm in 3 hours. Pilots use the same formula to work out ground speed, flight time and distance.

One speed distance time calculator for every use

Because speed is distance over time in every situation, this one calculator replaces a shelf of single-purpose tools:

• Car and driving calculator – a travel time calculator from distance and speed: enter the route distance and your expected average speed to get the driving time.
• Walking, running and treadmill calculator – the pace calculator output shows minutes per km alongside your speed.
• Bike and cycling calculator – find the average speed of a ride from your distance and moving time.
• Boat and marine calculator – pick nautical miles and knots; it does the job of the circular Portland speed time distance calculator (a slide rule sailors use): set any two of speed, time and distance and read off the third.
• Flight and aviation calculator – use ground speed in knots and distance in nm to estimate flight time. Air speed differs from ground speed by the wind component, so use ground speed.
• Average speed calculator – enter total distance and total time for the whole trip.

It solves constant or average speed only. If the speed changes steadily, you need the equations of motion with acceleration (v = u + at, s = ut + ½at²) instead.

Speed distance time questions for practice

Try these speed distance time questions without a calculator, then check the answers with the tool above:

1. A bus travels 180 km in 3 hours. What is its speed? (60 km/h)
2. A walker moves at 5 km/h for 90 minutes. How far do they go? (7.5 km)
3. How long does a 250 km journey take at 100 km/h? (2 h 30 min)
4. A car travels 25 m/s. What is that in km/h? (90 km/h)

The best way to learn speed distance time is to do a handful of questions like these by hand, using the triangle, until the formulas feel automatic.

Speed from a distance time graph

On a distance time graph, distance is on the y-axis and time on the x-axis. The speed is the gradient (slope) of the line: pick two points and divide the change in distance by the change in time. A straight line means constant speed, a steeper line means faster motion, and a flat horizontal line means the object is stationary. This topic comes up in class 9 science and in GCSE and KS3 maths.

How to work out speed distance time in your head

Round to friendly numbers and use minutes: at 60 km/h you cover 1 km per minute; at 90 km/h, 1.5 km per minute; at 120 km/h, 2 km per minute. So 45 km at 90 km/h takes 30 minutes. For speed distance time questions without a calculator, turn minutes into fractions of an hour: 15 min = ¼ h, 20 min = ⅓ h, 45 min = ¾ h.

Speed of light and sound

The same formula works at any scale. Sound travels at about 343 m/s in air, so thunder heard 3 seconds after lightning means the strike was about 1 km away. Light travels at 299,792 km/s and takes about 8 minutes 20 seconds to reach Earth from the Sun, 149.6 million km away.

Speed, distance, time explained

Speed tells you how much distance is covered in each unit of time. If a bus covers 60 km every hour, its speed is 60 km/h; in 2 hours it covers 120 km, and 30 km takes half an hour. Every speed, distance and time question is just this idea rearranged.

Speed equals distance over time: calculator formula

Textbooks write the same rule in several ways – speed is equal to distance upon time, speed is equal to distance by time, or speed = distance divided by time – and the calculator uses exactly that formula when you choose to find speed. To find distance it uses distance = speed x time, and to find time it divides distance by speed.

Distance = speed x time: calculator example

A cyclist rides at 18 km/h for 2 h 30 min. Convert the time to hours (2.5 h), then 18 × 2.5 = 45 km. Enter 18 km/h and 2 h 30 min and the calculator returns 45 km with each step shown.

Time calculator using speed and distance

As a time calculator using speed and distance, enter the distance and your average speed. A 350 km drive at 70 km/h takes 350 ÷ 70 = 5 hours; at 60 km/h it takes 5 h 50 min. Add stops separately, because the formula assumes you keep moving.

Speed distance time calculator: triangle or formula?

The triangle and the formula give the same answer. Use the speed distance time calculator triangle trick when you forget which way round to divide: cover the quantity you want and the triangle shows either a division (D over S or D over T) or a multiplication (S next to T).

Speed distance time calculator: running and walking pace

For runners, pace (minutes per km) is the upside-down version of speed. Running 10 km in 50 minutes is a speed of 12 km/h and a pace of 5:00 per km. A brisk walk is about 5 km/h, or 12 minutes per km, so the speed distance time calculator for walking shows a 3 km walk takes about 36 minutes. Used as a speed distance time pace calculator, enter distance and finish time to get speed, then divide 60 by the km/h figure for minutes per km.

On a treadmill, the display usually shows km/h. As a treadmill speed distance time calculator, enter 8 km/h and 45 minutes to get 6 km.

Portland speed time distance calculator instructions

A Portland-style circular speed time distance calculator has two rotating scales. To use it, turn the inner disc until the speed on the outer scale sits against the 60-minute (one hour) mark. Then, for any time on the inner scale, the distance covered is directly opposite it on the outer scale – and for any distance, the time is opposite it. At 12 knots, 30 minutes lines up with 6 nautical miles. The online calculator on this page gives the same answer with more precision and no alignment errors, and works as an air speed distance time calculator for pilots or a marine one for sailors.

Speed distance time calculator: light years and the speed of sound

A light year is a distance, not a time: the distance light travels in one year, about 9.46 trillion km. As a speed of light distance time calculator, enter 299,792,458 m/s as the speed and the distance to find the travel time – the Moon, about 384,400 km away, is 1.28 light-seconds from Earth. Proxima Centauri is 4.24 light years away, so light takes 4.24 years and a spacecraft at 17 km/s would take over 70,000 years. This calculator uses ordinary (non-relativistic) motion, so it is not a light speed travel time dilation calculator.

As a speed of sound distance time calculator, use 343 m/s in air: an echo heard 2 seconds after a shout comes from a wall 343 m away, because the sound travels there and back.

Calculate speed: distance time graph method

To calculate speed from a distance time graph, pick two points on a straight section, divide the change in distance by the change in time, and the answer is the gradient – which is the speed. If the graph goes from 0 m at 0 s to 100 m at 20 s, the speed is 100 ÷ 20 = 5 m/s. A curved line means the speed is changing; a flat line means the object has stopped.

Speed distance time non calculator questions

In exams you often meet speed distance time non calculator questions, where the numbers are chosen to divide neatly. Convert minutes to hours as fractions (15 min = ¼ h, 20 min = ⅓ h, 45 min = ¾ h) and the working stays simple:

1. A train travels 150 km in 1 h 15 min. Speed = 150 ÷ 1.25 = 120 km/h.
2. A walker at 6 km/h walks for 40 minutes. Distance = 6 × ⅔ = 4 km.
3. A car at 80 km/h covers 20 km. Time = 20 ÷ 80 = ¼ h = 15 minutes.
4. A cheetah runs 100 m in 4 s. Speed = 25 m/s = 25 × 3.6 = 90 km/h.

Speed distance time calculation practice

For more speed distance time calculation practice, make your own speed distance time worksheet free of charge: write ten questions like those above, solve them by hand, then check each one with the calculator. A speed distance time non calculator worksheet usually mixes all three types (find speed, find distance, find time) and one unit conversion. To calculate speed, distance and time at grade 6 level, stick to whole hours and km; later grades add minutes, m/s and average speed. The calculator's step-by-step solution doubles as an answer key for any speed distance time calculation worksheet or speed distance time online test you set yourself.

No speed distance time calculator app needed

You do not need a speed distance time calculator app: this page runs in any mobile browser and shows the full working with each answer.

Frequently asked questions

Last updated 2026-09-18