Why use this calculator
Exercise calorie figures are among the most over-trusted numbers in fitness, and the gap between what people believe they burn and what they actually burn explains a great deal of stalled progress. This calculator uses metabolic equivalents, the same basis as published activity tables, so the estimate is grounded in measured research rather than a machine's marketing.
Just as importantly, it puts the result in perspective: thirty minutes of running burns roughly what is in a muffin, which is genuinely useful to know before deciding that a workout has earned a large meal. Seeing the per-minute rate alongside the total also makes it obvious which activities are actually demanding and which just take a long time.
How to use it
- Enter your body weight, since energy cost scales almost directly with the mass you are moving.
- A heavier person burns meaningfully more for the same activity.
- Choose the activity that most closely matches what you did, and be honest about intensity, because the difference between an easy jog and a hard run is large in MET terms.
- Duration should be actual moving time rather than total session time, so exclude rest between sets, waiting at lights and time spent standing around.
- The result is best used for comparing activities rather than as a precise figure to eat back.
What each result means
- To burn one pound of fat
- How long this activity would take to burn 3,500 calories, the usual estimate for one pound of body fat. It shows why food intake usually matters more than exercise alone.
- Calories Burned
- Total energy used during the session. It includes the energy you would have burned at rest anyway, so the net additional burn is lower.
- Per Minute
- Burn rate for this activity, which is the fair basis for comparing activities of different lengths.
- Per Hour
- What an hour of this activity would cost, useful for planning a session against a weekly target.
- MET Value
- The activity's metabolic equivalent. How many times your resting rate it demands. Higher means more intense.
The formula
Calories burned = MET x body weight in kilograms x duration in hours
One MET is roughly the energy used sitting quietly. Running at a moderate pace is about 9.8 METs, cycling about 6.8, swimming about 7.0 and walking about 3.5. Because the formula scales with body weight, the same activity costs a 100 kilogram person about 25 per cent more than an 80 kilogram person.
How this number is used in practice
The figure includes energy you would have burned anyway. Sitting on the couch for thirty minutes still costs roughly 40 calories, so a 378 calorie run is nearer 340 calories of additional expenditure. This matters because fitness trackers and cardio machines report gross rather than net burn, which inflates the apparent reward of a session and makes eating it back a losing trade.
Consumer devices are worse than most people assume. Studies comparing wrist-worn trackers against laboratory measurement have found calorie estimates off by anywhere from a quarter to well over half, even where heart rate tracking itself is reasonably accurate. Cardio machines that do not know your weight are guessing outright. Use any of these figures for tracking trends across weeks, not for balancing a daily calorie ledger.
Worked examples
170 lb person running for 30 minutes
About 378 calories at 9.8 METs, roughly 12.6 calories a minute.
150 lb person cycling for 45 minutes
About 347 calories at 6.8 METs. Lighter body weight lowers the cost of the same activity.
200 lb person walking for 60 minutes
About 318 calories at 3.5 METs, which is why walking works best as volume rather than intensity.
When people use it
- Comparing the energy cost of different activities
- Planning session length to hit a weekly activity target
- Sanity-checking the figure a fitness tracker reports
- Understanding why exercise alone rarely changes weight much
- Estimating the energy cost of physical work rather than sport
Tips
- Subtract your resting burn to get the net figure. Roughly 1.3 calories a minute for an average adult.
- Do not eat back the full number. Estimates run high, and doing so erases most of a moderate deficit.
- Body weight drives the result, so the same session costs a heavier person substantially more.
- Use actual moving time rather than total session time; rest between sets is not exercise.
- Compare activities per minute rather than per session to see which is genuinely more demanding.
- Treat tracker and machine figures as trend data. Laboratory comparisons show errors of 25 per cent and more.
What it assumes, and where it stops being accurate
- Standard published MET values are used, which are population averages rather than personal measurements.
- Energy cost is assumed to scale linearly with body weight, which holds approximately rather than exactly.
- Fitness level, efficiency, terrain, altitude and temperature all affect actual cost and are not modelled.
- The figure is gross energy expenditure, including the resting burn you would have had anyway.
- Excess post-exercise oxygen consumption, the small extended burn after hard training, is not included.
Terms used on this page
- MET
- Metabolic equivalent of task. The ratio of an activity's energy cost to resting metabolism.
- Gross versus net burn
- Gross includes the resting energy you would have used anyway; net is the additional cost of the activity.
- EPOC
- Excess post-exercise oxygen consumption, the modest elevated burn in the hours after hard training.
- Energy balance
- The relationship between energy taken in as food and energy expended.
Questions people ask
- What is a MET value?
- The metabolic equivalent of task: how many times your resting metabolic rate an activity demands. One MET is roughly sitting quietly. Walking is about 3.5 METs, cycling around 6.8 and running about 9.8. MET values come from published research measuring oxygen consumption during activity, which makes them a better basis than a device's own estimate.
- How accurate are these estimates?
- Reasonable for comparing activities, poor as a precise personal figure. MET values are population averages and do not account for fitness, efficiency, terrain or temperature. Expect a real error of 10 to 20 per cent even before device error is considered, which is why these numbers suit trend tracking rather than calorie ledgers.
- Should I eat back the calories I burn?
- Partially at most, and usually less than you think. Estimates run high, the figure includes the resting burn you would have had anyway, and appetite tends to rise after exercise regardless. Eating back the full reported amount routinely erases a moderate deficit entirely.
- Why do fitness trackers show different numbers?
- Because each uses its own algorithm, and most rely on heart rate and movement rather than measured oxygen consumption. Independent studies have found consumer calorie estimates off by 25 per cent to well over 50 per cent, even where heart rate itself is tracked accurately. Use them for relative comparison across your own sessions.
- Does a heavier person burn more calories?
- Yes, and substantially. Energy cost scales with the mass being moved, so a 100 kilogram person burns roughly 25 per cent more than an 80 kilogram person doing the identical activity for the same time. It is also why the same run gets easier, and burns slightly less, as you lose weight.
Use this with
Calories Burned Calculator answers one part of the question. These pick up where it stops: BMR Calculator, Calorie Calculator, Running Pace Calculator and TDEE Calculator.
Where these figures come from
This calculation is jurisdiction-neutral arithmetic. No country-specific rules are applied.
- American College of Sports Medicine: resources. Exercise testing and prescription guidance
- Heart Foundation: physical activity and exercise. Activity guidance for adults
Calories Burned Calculator produces an estimate for general information. It is not financial, tax, medical, legal or engineering advice. read the full disclaimer. Spotted a wrong number? Report it and it gets fixed. The form picks up this calculator and the inputs you used.