Weight lifting calorie
calculator

Calories burned weight training, from your bodyweight, session effort, and total session time. Compendium MET values, imperial or metric — with the reason the labeled range is narrow and why much of the number is resting metabolism you'd have spent anyway.

How the math works

Two steps. A session-effort band has a MET value — its energy cost as a multiple of resting metabolism — from the Compendium of Physical Activities. A MET is then turned into calories by the standard metabolic constant (ACSM Guidelines, 2021): 1 MET = 3.5 mL O₂/kg/min, and about 5 kcal per litre of oxygen. It's the same engine as the walking-, running-, and swimming-calorie math; only the table changes. The 2011 Compendium (Ainsworth et al. 2011) prices resistance training in three effort bands — light or moderate (8–15 reps at varied resistance) 3.5 METs, heavy or explosive (squats) 5.0, and vigorous (power lifting or body building) 6.0. Enter your own MET if your session sits between the bands or outside them.

The net line strips the resting metabolism a MET already includes, using (MET − 1)/MET. That resting share is 1 / MET, and because resistance METs are low it is large: about 29% at the light/moderate 3.5-MET band and 17% at the vigorous 6.0 band — far bigger than a high-MET activity like rope jumping (~8.5%). Notice too how little the bands differ: the whole span from light/moderate to vigorous is only 1.71× (6.0 / 3.5), because every entry is a whole-session average that already includes the rest between sets.

Worked example

A 185 lb (83.9 kg) lifter does a vigorous free-weight session — power lifting or body building effort, 6.0 METs — for 45 minutes of total session time, counting the sets and the rest between them.

• Per minute: 6.0 × 3.5 × 83.9 / 200 = 8.81 kcal/min
• Session (gross): 8.81 × 45 = 396 kcal; per hour 529 kcal/h
• Session (net): the workout's own contribution is 330 kcal; the other ~66 kcal (17%) is resting metabolism

Now change the effort. Light or moderate (3.5 METs) drops the same 45 minutes to 231 kcal gross; heavy or explosive (5.0 METs) lands at 330 kcal gross. The vigorous session is only 1.71× the light/moderate one (6.0 / 3.5) — the whole labeled range — despite the far heavier bar the vigorous band implies, because rest is baked into every band. A lifter at a round 80 kg (176.4 lb) at vigorous effort for 45 minutes is 378 kcal gross, 315 net; at light/moderate, 220.5 kcal gross, 157.5 net. (Weight-training calories are unit-system-agnostic — kcal is universal — so the only imperial/metric axis is the bodyweight input, lb ↔ kg.)

When this calculator is wrong

A weight session's calorie burn is smaller than the bar implies, and it's mostly bookkeeping you'd have spent anyway: the Compendium prices all of resistance training in a narrow 3.5–6.0 MET band because every entry already averages in the rest between sets. The 2011 Compendium's three bands are light/moderate (3.5), heavy/explosive (5.0), and vigorous (6.0) METs — the whole span is only 1.71× (6.0 / 3.5). That narrowness is the point: each entry is a whole-session average, so a heavier bar does not buy a proportionally bigger number; what moves the burn is total session minutes and bodyweight. For the 185 lb lifter above, the three bands over 45 minutes are 231 → 330 → 396 kcal gross, and most of that is counted as gross. Strip the resting share a MET includes — large here, 29% at light/moderate down to 17% at vigorous — and the workout's own net is well under the headline. The error that dwarfs the band choice is time: enter total session time (sets plus rest), which is what the Compendium measured, and read the net, not the gross.

• Rest length moves you inside the band, not the bar. A long-rest strength session (three-to-five-minute rests between heavy singles) sits toward the low end; a short-rest hypertrophy or superset session sits toward the high end — at the same bar weight. The band is about session density, not load.
• The counter: the session number isn't the whole metabolic story. Heavy lifting raises post-exercise oxygen use (EPOC) and, over months, adds lean mass that lifts resting metabolism — effects a single-session MET can't see. But the EPOC bump is modest (tens of kcal, not the hundreds some marketing implies), and the muscle effect is slow. The real case for lifting in a deficit is that it protects the lean mass a diet would otherwise strip (Helms, Aragon & Fitschen 2014), not that the session burns like cardio.
• A MET is a lab group mean. It's blind to your lifts, your tempo, and your rest discipline, so two lifters at the "same" vigorous effort don't cost the same. The number is a planning estimate, not a measurement.

What to do with the result

Use the number to plan, then let the scale calibrate it. The net figure is the honest input when you're sizing what a lifting session adds to a deficit — at roughly 330 net kcal for 45 vigorous minutes (185 lb), three sessions a week is about 990 net kcal. At the classic (and optimistic) 3,500 kcal per pound, that's a bit over a quarter-pound a week from lifting alone, before the body adapts. The gross figure is the one to drop into a daily calorie budget.

Because the band is narrow, the way to spend more energy in the room is more total session minutes or shorter rests, not simply a heavier bar — but that trades against the point of heavy lifting, which is strength and lean-mass retention, not calorie burn. If calorie expenditure is the goal, cardio is the more efficient per-minute tool; keep lifting for what only lifting does. Then track your weight over two weeks against your intake and adjust by 100–200 kcal if it isn't moving as expected; your scale is a better measurement than any MET table.

Common questions

How many calories does weight lifting burn in an hour?

For a 185 lb (83.9 kg) lifter at a vigorous effort (6.0 METs), about 529 kcal/h gross. A heavy/explosive session (5.0 METs) and a light/moderate one (3.5 METs) run lower — over a 45-minute session the three come to about 396, 330, and 231 kcal gross respectively. The figure scales straight with bodyweight, so a 200 lb lifter burns about 200/185 = 1.08× these numbers at the same effort and time.

Does lifting heavier burn more calories?

Less than you'd expect. The 2011 Compendium prices the whole range of resistance training between just 3.5 and 6.0 METs — a 1.71× span from light/moderate to vigorous — because each entry is a whole-session average that already includes the rest between sets. A heavier bar usually means longer rests, which pulls the session back toward the low end. What reliably moves the number is total session minutes and bodyweight, not load.

Should I count the rest between sets?

Yes. A Compendium MET is measured on the whole activity bout, rest included, which is exactly why resistance training sits at only 3.5–6.0 METs rather than the higher figure a non-stop effort would score. Enter total session time — working sets plus the rest between them — not just time under tension. Counting only the working seconds and applying the same MET would understate the clock the MET was calibrated against.

Is the calorie number gross or net?

The headline is gross — the full MET-based figure, which includes the resting calories you'd have burned anyway. The "net" line strips that out using (MET − 1). Because resistance METs are low, the resting share (1 / MET) is large: about 29% at light/moderate (3.5), 20% at heavy (5.0), and 17% at vigorous (6.0). For fitting the session into your daily calorie budget the gross number is right; for sizing what the lifting added, use net.

Do you keep burning calories after lifting weights?

Some — resistance training raises post-exercise oxygen use (EPOC) for a while after you rack the bar, and this calculator's during-session number doesn't include it. But the effect is modest, usually tens of calories rather than the hundreds sometimes claimed, and it doesn't rescue a small session into a big one. Lifting's larger body-composition payoff is slower and indirect: the lean mass it builds and protects, which a single-session calorie count can't show.

Does weight training or cardio burn more calories?

Per minute, cardio usually wins. Vigorous lifting is 6.0 METs; a 6 mph run is about 9.8 METs and an 8 mph run about 11.8, so running burns roughly 1.6–2× the calories per minute. Weight training's value isn't the calories burned in the session — it's strength and the lean mass that cardio alone won't build, which is why keeping both in a program beats choosing one for the calorie number.