Estimate activity calories by time or distance
This calculator estimates the energy you spend during an activity in two ways. In the first, you choose an activity, enter how long you did it and your body weight. In the second, you enter a distance and a pace or speed for walking, running or cycling, and the page works out the time for you. Both routes end in the same arithmetic, which uses a MET value taken from a published table. For the default example, 45 minutes of moderate walking at 70 kg, the page shows about 209 gross kilocalories and 154 active kilocalories. The two figures mean different things, and the next sections explain how. The result is an estimate from population averages. It is not a measurement of what your body burned, and it is not a target for eating or for weight change.
Choose an activity and MET value
A MET, or metabolic equivalent of task, expresses how much energy an activity uses compared with sitting quietly. One MET is defined as an oxygen uptake of 3.5 millilitres per kilogram of body mass per minute, which is the conventional value for resting energy. An activity rated at 4 METs therefore uses about four times as much energy as rest. Walking at a moderate pace is 3.8 METs in the table used here, and running at about 5.1 miles per hour is 8.5.
The values come from the 2024 Adult Compendium of Physical Activities, an updated catalogue that assigns a MET and a five-digit code to each activity (Compendium site, Herrmann et al., 2024). The full catalogue has more than a thousand entries, so this page offers 30 of them across walking, hiking, running, cycling, gym work, swimming and housework. The list keeps each source code visible in the result, so you can check it against the original. Its scope is adults aged 19 to 59, which is why the age field has that limit. If your activity is not listed, the custom method lets you enter any MET from 1 to 25 that you have found yourself. The page does not rate that value or check it, so treat it as your own assumption.
Walking, running and cycling distance
Distance mode is for the three activities where a speed has a published MET. You enter a distance in kilometres, miles, metres or yards, then either a speed in km/h or mph or a pace per kilometre or per mile. The page converts everything to miles per hour internally, using 1 mile = 1.609344 km, and divides distance by speed to get the time.
Walking
The walking bands run from 1.7 to 4.2 miles per hour, with MET values from 2.3 to 5.5. The calculator accepts walking speeds from 1 to 4.4 mph. Beyond that range, no published band applies, and a person moving faster is probably not walking in the usual sense.
Running
The running bands run from 4.1 to 8 mph, with MET values from 6.5 to 12. Speeds from 4 to 8 mph are accepted. Faster running than that is outside the table, and the page says so rather than guessing a higher MET.
Cycling
The cycling bands run from 7.5 to 17.5 mph, with MET values from 4 to 12. The page accepts 5 to 19 mph. Cycling energy depends strongly on wind, terrain and bike type, none of which the source bands capture.
How the speed band is chosen
The Compendium lists discrete speeds, not a continuous curve. This calculator picks the band whose speed is nearest to yours, and when your speed sits exactly halfway between two bands it takes the lower one (for walking, 2.2 mph is chosen for 2.35 mph). That is a choice made for this page, not a rule published in the Compendium. The result table always shows the band that was used, so a speed of 3.1 mph appears as the 3.1 mph band with code 17190. If your speed falls outside the supported range, the page declines to give a number and suggests the duration method with a custom MET.
Gross calories versus active calories
Gross calories are the total energy spent during the activity, including the energy your body would have used anyway at rest. The formula is MET × 3.5 × weight in kg ÷ 200 × minutes. Active calories subtract one MET of resting energy, using (MET − 1) in place of MET, so they show only the extra energy that the activity needed. The resting part is 3.5 × weight ÷ 200 × minutes. For the walking example, gross is 209.5 kcal, the resting part is 55.1 kcal and the active part is 154.4 kcal, so the two add up exactly. The page also shows gross energy in kilojoules, using 1 kcal = 4.184 kJ.
The distinction matters for planning. If you estimate your daily energy by taking a resting figure and multiplying it by an activity factor, that factor already includes typical exercise. Adding a gross calories figure on top would count the resting energy twice. To compare a day's activity with your resting needs, see the BMR versus daily energy explanation, which shows resting energy from three named formulas. Nothing on this page predicts how many kilograms you will lose or gain.
Worked examples and unit conversions
Take a 70 kg adult walking for 45 minutes at 3.8 METs. Energy per minute at rest is 3.5 × 70 ÷ 200 = 1.225 kcal, so 45 minutes of rest is 55.125 kcal. Gross is 3.8 × 55.125 = 209.475 kcal and active is 2.8 × 55.125 = 154.350 kcal. Now take the same person running 30 minutes at 8.5 METs: the resting part is 36.750 kcal, gross is 312.375 kcal and active is 275.625 kcal.
Weight scales the answer in a straight line. The same 45-minute walk for an 85 kg person gives 254.4 gross kcal, which is 21.4% more than at 70 kg because 85 is that much larger than 70. Distance works the same way. A 5 km walk at 5 km/h takes 60 minutes. Entered as 3.107 miles per hour, which is almost exactly the same speed, it selects the same band and gives 279.3 gross kcal, matching the 279.3 kcal from the km/h entry. Active energy for that walk is 205.8 kcal. If you work in pounds, the page converts with 1 lb = 0.45359237 kg and keeps the exact kilograms when you switch units.
A few practical habits keep the estimate honest. Enter your current body weight, not a goal weight, because the energy cost scales with the mass you actually move. Enter the time you were really active, not the time on the clock including rests, queueing or stretching. For an interval session, it is usually better to split the work into its harder and easier parts and add the results than to apply one average MET to the whole hour. Where the list does not contain your activity, choose the closest one and say so in your notes, or enter a custom MET from a source you trust.
Why activity estimates differ
Two reputable calculators can give different numbers for the same walk, and so can your watch. Several things drive the gap. Each source assigns METs to slightly different speed ranges and intensities. Some tools use 3.5 millilitres of oxygen per kilogram per minute as one MET, while others use one kilocalorie per kilogram per hour, which is a little different. Some tools show gross figures and others net. A watch adds sensors for heart rate and movement, and its own model of your fitness, which a table cannot know.
There are also real differences between people that a MET table averages away. Fitness, body composition, walking economy, terrain, temperature, wind and carrying a load all change the energy needed for the same speed. None of them is in the inputs here. Heart rate is one way to describe how hard the effort felt to your body, and the target heart rate zones page explains how those zones are calculated. For running, the pace and distance calculator converts between pace, speed and time. Strength training is rated here by a single MET for the whole session, which hides the rest periods; if you want to estimate a lift, use the one rep max calculator to estimate a one rep max from a completed set, which is a different question from energy cost.
The best use of the estimate is comparison. Two walks, or a walk and a ride of the same length, can be set side by side on the same assumptions, and the difference between them is more meaningful than either absolute number. The comparison breaks down if the assumptions change between entries, so keep the weight and the activity definition the same when you compare. Nothing here tells you how much to eat, and a calorie figure from an activity page should not be used to set a deficit or a surplus without advice from a qualified professional who knows your health.
From calories burned to daily energy
An activity estimate is one part of total daily energy. To put it in context, the calorie and TDEE calculator estimates maintenance calories from your resting energy and a named activity level, in kcal and kJ.
MET sources, populations and limits
The MET values are taken from the 2024 Adult Compendium, and the source codes appear in the results. The Compendium describes adults aged 19 to 59, so the calculator does not offer figures for younger people or for older adults, whose energy cost for the same activity can differ. It does not model grade, wind, load, electric bikes, swimming distance or sports not in the list. The speed-band rule described above is an interpolation choice made for this page. A custom MET is whatever you enter. The estimate is meant for general education, not for managing a medical condition, and it is not a calorie prescription. The sources were last checked on 8 November 2026.
If you enter a custom MET, the page treats it exactly as it treats a preset: it multiplies by your weight and the time, using the same formula. It cannot check whether the value is sensible. A MET below 1 is rejected because it would mean using less energy than resting, and very high values should be checked against the source you took them from. The Compendium is a reference table of typical values for groups of people, so a custom value from it, or from a study, is still an average and not a measurement of you.
Calories burned questions
Does this include resting calories?
The gross figure does, because it is the total energy spent during the activity. The active figure removes the resting part, equal to one MET, so it shows only the extra energy.
How many calories does walking burn?
It depends on your weight, the time and the pace. At 70 kg, 45 minutes at 3.8 METs is about 209 gross kilocalories. A heavier person, a longer walk or a brisker pace raises the number in proportion.
Why does my watch disagree?
A watch uses its own sensors and its own model, while this page uses a published table of averages. Neither is the measured truth, so do not assume one of them is the correct one. Compare like with like, such as gross against gross.
Can I add this to my daily calorie target?
Be careful. If your daily estimate already includes an activity factor, adding this figure counts exercise twice. If you start from resting energy alone, use the active figure rather than the gross one.
Can it calculate swimming or cycling?
Cycling distance works for speeds from 5 to 19 mph. Swimming is available only by duration, using the slow and fast freestyle presets, because a swimming distance is not converted to a MET here.