Calories burned swimming or running? Free swim and running calorie calculator
Pick swim or run. Add your stroke and lengths or minutes, or your distance and pace, plus your weight. Takes 10 seconds.
- Published MET values from the 2024 Adult Compendium of Physical Activities
- UK pool lengths, 5k to marathon, weight in kg or stone
- By James Gonzo at JG Fitness, personal trainer and swim coach
Your estimate
Add your body weight to see your number.
How many calories does swimming burn?
It depends on three things: your stroke, how hard you swim and your body weight. Here are the calories burned swimming for 30 minutes, worked out from the Compendium values.
| Weight | Crawl easy (5.8) | Crawl steady (8.0) | Breaststroke rec. (5.3) | Backstroke rec. (4.8) | Butterfly (13.8) |
|---|---|---|---|---|---|
| 60 kg | 183 | 252 | 167 | 151 | 435 |
| 70 kg | 213 | 294 | 195 | 176 | 507 |
| 85 kg | 259 | 357 | 237 | 214 | 616 |
| 100 kg | 305 | 420 | 278 | 252 | 725 |
kcal in 30 minutes. MET values in brackets. As a cross-check, Swim England quotes about 200 (breaststroke), 250 (backstroke), 300 (freestyle) and 450 (butterfly) calories per 30 minutes, without giving a body weight. Our 70 to 85 kg figures are in the same range.
Calories burned swimming by stroke
Butterfly burns the most per minute (MET 13.8). Recreational backstroke burns the least of the four main strokes (4.8). Breaststroke and backstroke more or less double when you swim them hard, at 10.3 and 9.5.
Per kilometre is more interesting. For a 70 kg swimmer doing front crawl at the Compendium's default paces:
Faster swimming burns more per minute, but you're in the water for less time, so the per-km figures end up close. A 25 m length is about 5 kcal for a 70 kg swimmer.
Does cold water swimming burn more calories?
The Compendium doesn't have a separate value for cold water swimming, so this calculator doesn't add anything for it. What we do have is one study: White and colleagues (2005) found that people used similar energy exercising in 20°C and 33°C water, but ate more afterwards when the water was cooler.
So if you swim outdoors in winter and come out starving, that fits the research. It doesn't mean you burned a lot more.
Running calorie calculator: how many calories does running burn?
For running, speed is what matters. The running calorie calculator turns your distance and time (or pace) into a speed, then uses the Compendium's value for the nearest level-running band. Here's what that looks like for a 70 kg runner.
| Compendium speed | Pace /km | Pace /mile | MET | Code | kcal, 30 min | kcal per km |
|---|---|---|---|---|---|---|
| 4 to 4.2 mph | 9:06 | 14:38 | 6.5 | 12028 | 239 | 72 |
| 4.3 to 4.8 mph | 8:12 | 13:11 | 7.8 | 12029 | 287 | 78 |
| 5.0 to 5.2 mph | 7:19 | 11:46 | 8.5 | 12030 | 312 | 76 |
| 5.5 to 5.8 mph | 6:36 | 10:37 | 9.0 | 12045 | 331 | 73 |
| 6 to 6.3 mph | 6:04 | 9:45 | 9.3 | 12050 | 342 | 69 |
| 6.7 mph | 5:34 | 8:57 | 10.5 | 12060 | 386 | 72 |
| 7 mph | 5:20 | 8:34 | 11.0 | 12070 | 404 | 72 |
| 7.5 mph | 4:58 | 8:00 | 11.8 | 12080 | 434 | 72 |
| 8 mph | 4:40 | 7:30 | 12.0 | 12090 | 441 | 69 |
| 8.6 mph | 4:20 | 6:59 | 12.5 | 12100 | 459 | 66 |
| 9 mph | 4:09 | 6:40 | 13.0 | 12110 | 478 | 66 |
| 10 mph | 3:44 | 6:00 | 14.8 | 12120 | 544 | 68 |
70 kg runner, level ground. Paces are the middle of each band. Below 4 mph the Compendium lists jogging at 2.6 to 3.7 mph (MET 3.3, code 12026). The calculator uses that too, and flags anything slower. Hills, treadmills and trails have their own values, which aren't used here.
Notice the last column: per kilometre, the number barely moves with speed. Like swimming, a faster run burns more per minute but takes less time.
How the swim and running calorie calculator works
One MET is about 3.5 ml of oxygen per kg of body weight per minute, as defined in the Compendium. Dividing by 200 converts that to kcal per minute (the standard ACSM equation).
- Lengths: distance = lengths × pool length. If you don't give a time, minutes = distance ÷ the default front-crawl pace for your effort (easy ~34 m/min, steady ~46 m/min, fast ~69 m/min). These come from the Compendium descriptions. For other strokes we ask for your time, because the Compendium doesn't give a pace for them.
- Your own swim pace: we use the front-crawl band nearest to your pace.
- Running: we use the level-running speed band nearest to your speed.
- Weight: 1 stone = 6.35029 kg and 1 lb = 0.453592 kg.
These are gross figures, so they include what you'd burn sitting still. The result is an estimate, not a measurement: your real burn varies with technique, rests and body size. Totals are rounded to the nearest 5 kcal.
Swimming MET values used (2024 Compendium)
| Activity | Code | MET |
|---|---|---|
| Front crawl, easy (slow, 30 to 45 yd/min) | 18292 | 5.8 |
| Front crawl laps, slow recreational | 18240 | 5.8 |
| Front crawl, steady (medium, ~50 yd/min) | 18290 | 8.0 |
| Front crawl laps, fast vigorous | 18230 | 9.8 |
| Front crawl, fast (~75 yd/min) | 18280 | 10.5 |
| Breaststroke, recreational | 18265 | 5.3 |
| Breaststroke, training or competition | 18260 | 10.3 |
| Backstroke, recreational | 18255 | 4.8 |
| Backstroke, training or competition | 18250 | 9.5 |
| Butterfly, general | 18270 | 13.8 |
| Sidestroke, general | 18320 | 7.0 |
| Leisurely, not lap swimming | 18310 | 6.0 |
| Lake, sea or river | 18300 | 6.0 |
| Treading water, moderate | 18350 | 3.5 |
| Treading water, fast | 18340 | 9.8 |
Herrmann SD, Willis EA, Ainsworth BE et al. 2024 Adult Compendium of Physical Activities. Water activities · Running.
What to eat around your swim and run
Simple, sourced guides from a personal trainer and swim coach. No diets, no fads.
Swim fuel
What to eat before swimming
Foods and timings for an adult pool session, plus what to eat after swimming.
Read the guide →Swim fuelShould you eat before swimming?
A yes-or-no answer for early swimmers, after-work lessons and anyone wondering about swimming fasted.
Read the guide →Swim fuelHow long after eating can you swim?
A myth check on the old “wait 30 minutes” rule, plus a simple timing table for comfort.
Read the guide →Run fuel
What to eat before a run
A timing ladder for everyday training runs: what to eat 2 to 3 hours before, 1 to 2 hours before and when you've only got minutes.
Read the guide →Run fuelWhat to eat after a run
Carbs to refuel, protein to repair, fluids to rehydrate. And how much any of it matters after an easy jog.
Read the guide →Run fuelShould you eat before running?
The yes-or-no decision, by type of run, and what the research actually says about running fasted.
Read the guide →Want to swim better, not just burn more?
Want a smoother, fitter front crawl? Try James's free 4-week pool plan and drill library at JG Fitness. Runner? There's a running strength plan too.
Swim and running calorie questions
How many calories does swimming burn in 30 minutes?
It depends on your stroke, effort and weight. For example, a 70 kg person doing easy to steady front crawl burns about 215 to 295 kcal in 30 minutes, using the 2024 Compendium values. The table above shows other strokes and weights.
Which swimming stroke burns the most calories?
Butterfly has the highest Compendium MET of the main strokes (13.8). Recreational backstroke is the lowest of the four (4.8).
How many calories does one length burn?
About 4 to 8 kcal per 25 m length of front crawl for someone weighing 60 to 100 kg, at the Compendium's default paces. Pick “Lengths” in the calculator for your own figure.
Is swimming or running better for burning calories?
Per minute, it depends on how hard you go. Using the Compendium values, steady front crawl (~50 yd/min) is 8.0 MET and running at 6 to 6.3 mph (about a 10-minute mile) is 9.3 MET. Recreational breaststroke is 5.3 and butterfly is 13.8. The calculator gives you both figures for your own sessions.
How does the running calorie calculator pick a value?
It works out your speed from your distance, time or pace, then uses the 2024 Compendium MET for the nearest level-running speed band. Hills, treadmills and trails have their own values, which this calculator doesn't use.
Why does my watch say something different?
Watches use their own formulas, often with your heart rate. Both are estimates.
Does swimming in cold water burn more calories?
The Compendium has no separate cold-water value. One study (White et al., 2005) found people used similar energy swimming in 20°C and 33°C water, but ate more afterwards when the water was cooler.
Is this calculator accurate?
It uses published averages, so treat the number as an estimate, not a measurement. Your real burn varies with technique, rests and body size.
Sources
- Herrmann SD, Willis EA, Ainsworth BE et al. 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science, 2024. pmc.ncbi.nlm.nih.gov/articles/PMC10818145
- 2024 Adult Compendium, Water activities (codes 18xxx), opened 1 Nov 2026. pacompendium.com/water-activities
- 2024 Adult Compendium, Running (codes 12xxx), opened 1 Nov 2026. pacompendium.com/running
- Swim England, Best swimming stroke for weight loss (opened 1 Nov 2026). www.swimming.org/justswim/best-swimming-stroke-for-weight-loss
- White LJ et al. Increased caloric intake soon after exercise in cold water. Int J Sport Nutr Exerc Metab 2005;15(1):38-47. pubmed.ncbi.nlm.nih.gov/15902988