Health calculator

Free calories burned calculator

See how many calories any workout burns. Enter the activity's MET value, your weight in kg, and how long you exercised — the calories burned calculator multiplies MET × kg × hours and returns your estimate, with a MET table for walking, running, cycling, swimming, weights, and HIIT, updated live, as you type.

InputsLive
Activity
Body weight
kg
Duration
hr
Result
Calories burned
245 kcal
Walking (moderate) · 70 kg · 1 hr
Calories burned245 kcal
Per minute4.1 kcal
MET value3.5
Duration1 hr

Calorie estimates vary based on fitness level, intensity, and individual metabolism. Wearable devices may be more accurate for personal use.

Results are estimates. Consult a professional.

Definition

How the calories burned calculator works

The calories burned calculator estimates how much energy an activity costs using three inputs: the MET value of what you're doing, your body weight in kilograms, and how long you do it. Multiply those together and you have a solid estimate of the calories burned — the same method exercise scientists use. The calculator above does the arithmetic the instant you enter a MET value, your weight, and a duration.

calories burned = MET × weight(kg) × time(hours)

Because the formula is a straight multiplication, the result scales cleanly: double the time and you double the calories; weigh twice as much and you burn roughly twice as much for the same activity. The only judgement call is the MET — pick the value that matches your activity and its intensity, and the estimate falls into place.

It helps to know what the number means. The figure the calculator returns is the total energy your body spends during the activity — it already includes the calories you would have burned just sitting there, not only the extra cost of moving. That is why a short, gentle session still shows a meaningful number, and why this estimate is the right input for comparing one workout against another rather than for isolating the 'exercise-only' calories. Keep your weight in kilograms and your time in hours and the result is directly comparable across every activity in the table below.

The key input

What is a MET?

A MET — metabolic equivalent of task — is how exercise science measures intensity. One MET is the energy your body uses sitting quietly at rest, defined as burning about 1 calorie per kilogram of body weight per hour. Everything else is measured relative to that resting baseline.

So an activity rated at 8 METs burns roughly eight times as much energy per minute as sitting still. Walking briskly is about 3.5 METs; running is 8 to 12; sleeping is below 1. The whole point of the MET scale is that it lets one number describe an activity's intensity for everyone, then your own weight and time turn it into a personal calorie figure.

A unit of exercise intensity. 1 MET = the energy you burn at complete rest, about 1 calorie per kg of body weight per hour.
Below 3 METs — slow walking, light housework, stretching.
3 to 6 METs — brisk walking, easy cycling, doubles tennis. The range public-health guidelines target.
Above 6 METs — running, fast cycling, swimming laps, HIIT, jumping rope.
Reference

MET values for common activities

These are standard MET values from the Compendium of Physical Activities, the reference exercise physiologists use. Find your activity, read across to the MET value, and enter that number in the calculator's MET field. Where an activity spans a range, intensity is the driver — the harder you go, the higher the MET.

ActivityIntensityMET value
Walking, slow (2 mph)Light2.8
Walking, brisk (3.5 mph)Moderate4.3
Cycling, leisure (10–12 mph)Moderate6.8
Swimming, leisurelyModerate6.0
Weight training, generalModerate3.5
Weight training, vigorousVigorous6.0
Jogging (5 mph)Vigorous8.3
Running (6 mph)Vigorous9.8
Running, fast (8 mph)Vigorous11.8
Cycling, fast (14–16 mph)Vigorous10.0
Swimming laps, vigorousVigorous9.8
HIIT / circuit trainingVigorous8.0

Source: Compendium of Physical Activities (Ainsworth et al.). Use the value that matches your real intensity.

Pick the honest MET
When in doubt, choose the lower MET. Most people overestimate how hard they work, and a too-high MET inflates the calorie estimate. A genuine 'brisk' beats an aspirational 'fast' every time.
Worked example

A worked example using the calories burned calculator

Example: a 70 kg runner, 30 minutes at 6 mph

Sam weighs 70 kg and goes for a 30-minute run at a steady 6 mph. Here is the exact path the calculator follows — pick the MET, set the weight, set the time, then multiply.

  1. Find the MET. Running at 6 mph is 9.8 METs in the table above — that's the number Sam enters in the MET field.
  2. Enter the weight. Sam's body weight is 70 kg.
  3. Enter the time in hours. 30 minutes is half an hour, so 0.5 hours.
  4. Multiply. calories = 9.8 × 70 × 0.5 = 343 calories.
≈ 343 calories burned
That 30-minute run costs Sam about 343 calories. Run for a full hour instead and the figure doubles to roughly 686; weigh 90 kg rather than 70 and the same half-hour run burns about 441 — exactly the scaling the MET × kg × hours formula predicts.
The two personal levers

How weight and duration change calories burned

The MET sets the intensity, but your two personal inputs — weight and duration — decide the final number, and both act in a straight line.

  • Weight is a direct multiplier. Moving a heavier body costs more energy, so a 90 kg person burns about 29% more than a 70 kg person doing the identical activity for the identical time. This is why the same workout shows different calorie counts for different people.
  • Duration is the other direct multiplier. Twice the time means twice the calories, every time. A longer easy walk can out-burn a short hard sprint simply because it runs for longer.
Body weight30 min brisk walk (4.3 MET)30 min run (9.8 MET)
55 kg118 cal270 cal
70 kg151 cal343 cal
85 kg183 cal417 cal
100 kg215 cal490 cal

Same activity and duration, different body weights — calories scale directly with kilograms.

Head to head

Calories burned walking vs running

Running burns far more calories per minute than walking — its MET (around 9.8) is more than double a brisk walk's (around 4.3), so minute for minute running burns roughly two to three times as much. For the same 30 minutes, a 70 kg person burns about 151 calories walking briskly versus about 343 running.

But the picture shifts when you compare the same distance rather than the same time. Covering a mile on foot costs a fairly similar amount of energy whether you walk or run it — running just gets you there faster, so it burns more per minute but takes fewer minutes. The practical takeaways:

  • Short on time? Running burns more in the window you have.
  • Going by distance? Walking and running a mile end up close, so walking is the gentler way to burn a similar amount.
  • Sustainability matters. Walking is lower-impact and easier to do daily, which often makes it the bigger calorie burner over a whole week.

To convert your steps into both distance and calories, use the steps to calories calculator, and to work out your speed from a time and distance, the pace calculator does it instantly.

At a glance

Calories burned in 30 minutes by activity

To make the MET values concrete, here is roughly what each activity burns in a 30-minute session for three common body weights, straight from MET × kg × 0.5. Read it as a quick reference, then use the calculator above for your own exact weight and duration.

Activity (MET)55 kg70 kg85 kg
Walking, brisk (4.3)118 cal151 cal183 cal
Weight training (3.5)96 cal123 cal149 cal
Swimming, leisurely (6.0)165 cal210 cal255 cal
Cycling, leisure (6.8)187 cal238 cal289 cal
HIIT / circuit (8.0)220 cal280 cal340 cal
Running, 6 mph (9.8)270 cal343 cal417 cal
Cycling, fast (10.0)275 cal350 cal425 cal
Running, 8 mph (11.8)325 cal413 cal502 cal

Calories for a 30-minute session = MET × weight(kg) × 0.5. Higher MET and higher weight both raise the burn.

Two patterns stand out. Within a column, intensity dominates — running burns more than double what a brisk walk does for the same half hour. Across a row, the heavier person always burns more for the identical activity, because weight is a direct multiplier in the formula.

Reality check

How accurate is the calories burned calculator?

A MET-based estimate is well-grounded but not a measurement. For steady-state cardio done at a known intensity, it typically lands within about 10–20% of the truth. The arithmetic is exact; the uncertainty lives in the inputs and in how well a single MET captures your effort. Several things move your real burn away from the number on screen:

  • MET values are averages. The Compendium figure is for a typical person; your efficiency, fitness, and terrain all shift the real cost.
  • Body composition is invisible to the formula. MET × kg uses your weight, not how much of it is muscle — two people at the same weight can burn slightly differently.
  • Intensity intervals and EPOC aren't captured. HIIT and heavy weight training keep your metabolism elevated after you stop (the 'afterburn'), which a steady MET doesn't include — so those estimates run a little low.
  • The figure already includes your resting burn. A MET counts total energy during the activity, including the calories you'd have burned just sitting there, so it isn't purely the 'extra' from exercising.
Calculator vs wearable

Calculator vs fitness tracker estimates

It's natural to assume your watch is more accurate than a formula — but the research is humbling. A widely cited Stanford study of seven popular wrist trackers found that while they measured heart rate well, their calorie estimates were off by about 27–93%, with a median error near 30%. None met the 10% accuracy bar.

A MET-based estimate and a wearable are both approximations. The wearable adds your heart rate and movement, which can help for messy, variable workouts; the calculator is transparent and consistent. For steady, well-defined activities, the MET method is often as reliable as the watch — and you can see exactly how it got the number.

The honest way to use any calorie figure — formula or wearable — is as a consistent yardstick, not gospel. Pick one method, track the trend, and let the scale be the final word over a few weeks.

Putting it to work

Using calories burned for weight loss

Calories burned is only one half of the energy-balance equation. Weight change is driven by burn versus intake: eat fewer calories than you burn in a day and you lose, eat more and you gain. A single workout's burn is small against your total daily expenditure, so don't bank on out-exercising your diet.

To see the full picture, the TDEE calculator estimates your total daily energy expenditure — everything you burn in 24 hours, not just one session — and the calorie calculator turns a weight goal into a daily intake target. Use this page to estimate a workout's burn, and those two to set the budget it fits into.

3,500 calories ≈ 1 pound
As a rough planning rule, a deficit of about 3,500 calories corresponds to roughly a pound of fat. That's a guideline, not a law — metabolism adapts — but it shows why consistent small differences matter more than any single workout.
Methodology

Formula and sources

This calculator uses the standard MET method, calories = MET × weight(kg) × time(hours), where one MET is defined as 1 kcal per kg of body weight per hour. MET values follow the Compendium of Physical Activities (Ainsworth BE et al.), the reference dataset of energy costs for hundreds of activities. Tracker-accuracy figures come from the Stanford Medicine study of consumer wrist wearables (Shcherbina et al., Journal of Personalized Medicine, 2017).

Compendium of Physical Activities (Ainsworth et al.); Stanford wearable accuracy study, Shcherbina et al. (2017).
Questions

Frequently asked questions about the free calories burned calculator

A calories burned calculator is a free online tool that helps you calculate calories burned from MET value, weight, and duration. MET = metabolic equivalent. Walking ≈ 3, running ≈ 8-12, cycling ≈ 6-10. It runs entirely in your browser with instant results and no sign-up.
The standard method multiplies three things: the MET value of the activity, your body weight in kilograms, and the time in hours — calories = MET × weight(kg) × time(hours). A MET is the metabolic equivalent of the task, where 1 MET equals about 1 calorie per kilogram of body weight per hour at rest. So a 70 kg person running at 9.8 METs for half an hour burns 9.8 × 70 × 0.5 ≈ 343 calories.
A MET, or metabolic equivalent of task, is a unit of exercise intensity. One MET is the energy you burn sitting quietly — roughly 1 calorie per kilogram of body weight per hour. An activity rated at 8 METs burns about eight times as much energy per minute as resting. Walking briskly is about 4.3 METs, running 8–12, and light activity under 3.
Running burns more per minute — its MET (around 9.8) is more than double a brisk walk's (around 4.3), so for the same 30 minutes a 70 kg person burns about 343 calories running versus 151 walking. But over the same distance the two are closer, because running just covers the mile faster. Walking is lower-impact and easier to sustain daily.
For steady-state cardio at a known intensity, a MET-based estimate is typically within about 10–20% of the truth. The arithmetic is exact; the uncertainty is in the inputs — MET values are population averages, and they don't capture body composition or the afterburn (EPOC) from HIIT and heavy lifting, which makes those estimates run slightly low.
Not for calories. A Stanford study of seven popular wrist trackers found their calorie estimates were off by roughly 27–93%, with a median error near 30% — none met a 10% accuracy bar, even though they measured heart rate well. A transparent MET-based estimate is often as reliable as a wearable for steady, well-defined activities.
Usually not. A single workout's burn is small against your total daily energy expenditure and against how easily calories are eaten back. Weight change is driven by total burn versus total intake, where roughly a 3,500-calorie deficit corresponds to about a pound of fat. Use the burn figure alongside your TDEE and calorie targets rather than as a licence to eat more.
About

About this calories burned calculator

This calories burned calculator runs entirely in your browser. The MET value, weight, and duration you enter never leave your device — nothing is sent to a server, logged, or shared. It applies the standard MET formula, calories = MET × weight in kilograms × time in hours, using MET values from the Compendium of Physical Activities, updating instantly on every change.

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