Calories burned swimming: by stroke, minutes or lengths
Add your weight, then pick your stroke, effort and minutes or lengths. Water aerobics, aqua jogging and water walking are in there too.
- 2024 Adult Compendium values for 12 strokes and water activities
- UK pool lengths, weight in kg, stone or pounds
- By James Gonzo at JG Fitness, personal trainer and swim coach
Work out calories burned swimming
Your estimate
Add your body weight to see your number.
Running instead? The running calorie calculator handles pace, hills, a backpack and over-60s.
On this page: Calories burned swimming · Per hour · Water aerobics · Swimming vs running · Weight loss · FAQ
Calories burned swimming: how many calories does swimming burn?
Three things decide it: which stroke you swim, how hard you swim it and how much you weigh. 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 (9.4 st) | 185 | 250 | 165 | 150 | 435 |
| 70 kg (11.0 st) | 215 | 295 | 195 | 175 | 505 |
| 85 kg (13.4 st) | 260 | 355 | 235 | 215 | 615 |
| 100 kg (15.7 st) | 305 | 420 | 280 | 250 | 725 |
kcal in 30 minutes of continuous swimming, rounded to the nearest 5. 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 breaststroke and front crawl figures for 70 to 85 kg are close to these. Our backstroke comes out lower and butterfly higher, because the Compendium rates recreational backstroke low (4.8) and butterfly high (13.8).
Calories burned swimming by stroke and time
How long you swim matters as much as which stroke. These figures are for a 70 kg swimmer over 20 minutes to an hour. Use the swimming calorie calculator for your own weight, minutes or lengths.
| Stroke (MET) | 20 min | 30 min | 45 min | 60 min |
|---|---|---|---|---|
| Front crawl, steady (8.0) | 195 | 295 | 440 | 590 |
| Front crawl, easy (5.8) | 140 | 215 | 320 | 425 |
| Breaststroke, recreational (5.3) | 130 | 195 | 290 | 390 |
| Backstroke, recreational (4.8) | 120 | 175 | 265 | 355 |
| Butterfly (13.8) | 340 | 505 | 760 | 1,015 |
| Breaststroke, training (10.3) | 250 | 380 | 570 | 755 |
| Water aerobics, general (5.5) | 135 | 200 | 305 | 405 |
| Aqua jogging, moderate (7.5) | 185 | 275 | 415 | 550 |
kcal for 70 kg, rounded to the nearest 5, from the 2024 Adult Compendium. Long rests between lengths bring the real number down.
Calories burned swimming per km and per length
Of the four main strokes, butterfly burns the most per minute (MET 13.8); only elite-pace front crawl, over 90 yards a minute, is rated higher (14.5). Recreational backstroke burns the least (4.8). Breaststroke and backstroke roughly 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 of steady crawl 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) had 11 men cycle for 45 minutes in 20°C and in 33°C water. They used similar energy both times (about 505 and 517 kcal), but ate 44% 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.
Calories burned swimming per hour, by stroke and weight
An hour of non-stop swimming is a long session for most people, but it's a handy way to compare strokes. Heavier swimmers burn more, because there's more body to move.
| Stroke (MET) | 60 kg | 70 kg | 85 kg | 100 kg |
|---|---|---|---|---|
| Front crawl, easy (5.8) | 365 | 425 | 520 | 610 |
| Front crawl, steady (8.0) | 505 | 590 | 715 | 840 |
| Front crawl, fast (10.5) | 660 | 770 | 935 | 1,105 |
| Breaststroke, recreational (5.3) | 335 | 390 | 475 | 555 |
| Breaststroke, hard (10.3) | 650 | 755 | 920 | 1,080 |
| Backstroke, recreational (4.8) | 300 | 355 | 430 | 505 |
| Backstroke, hard (9.5) | 600 | 700 | 850 | 1,000 |
| Butterfly (13.8) | 870 | 1,015 | 1,230 | 1,450 |
| Sidestroke (7.0) | 440 | 515 | 625 | 735 |
| Leisure swimming (6.0) | 380 | 440 | 535 | 630 |
| Treading water, moderate (3.5) | 220 | 255 | 310 | 370 |
kcal per hour, rounded to the nearest 5. 2024 Adult Compendium values. If your hour includes rests at the wall, count only the swimming minutes in the calculator.
Water aerobics, aqua jogging and water walking
Not everyone in the pool is swimming lengths, and those calories count too. Water aerobics classes, aqua jogging (running in deep water, usually with a float belt) and walking in the shallow end all have their own Compendium values, and they're all in the calculator.
Water pushes back in every direction, so you're working against resistance the whole time while your weight is supported. That's why these sessions suit people coming back from injury, older swimmers and anyone whose knees don't love running. Runners use aqua jogging to keep fit while they rest an injury, because it copies the running action without the landing.
How much they burn depends on effort. A gentle water walk is rated 2.5 MET, much like a slow stroll, while vigorous water jogging and very fast water running reach 9.8, close to a 10-minute-mile run on land. A general water aerobics class sits at 5.5, and a high-intensity class at 7.5.
In the calculator, “Easy”, “Steady” and “Hard” map to the Compendium entries in the table. The result always tells you which entry it used.
Water activity MET values (2024 Compendium)
| Activity | Code | MET | kcal, 30 min at 70 kg |
|---|---|---|---|
| Water walking, light, slow | 18367 | 2.5 | 90 |
| Water aerobics, resistance exercises | 18356 | 3.8 | 140 |
| Water walking, moderate | 18368 | 4.8 | 175 |
| Water aerobics, general | 18355 | 5.5 | 200 |
| Water running, 30 steps/min, slow | 18374 | 6.5 | 240 |
| Water walking, vigorous, brisk | 18369 | 6.8 | 250 |
| Water aerobics, high intensity | 18358 | 7.5 | 275 |
| Water running, 40 steps/min, moderate | 18375 | 7.5 | 275 |
| Water running, 50 steps/min, fast | 18376 | 8.5 | 310 |
| Water jogging, vigorous | 18366 | 9.8 | 360 |
| Water running, 60 steps/min, very fast | 18377 | 9.8 | 360 |
| Water polo | 18360 | 10.0 | 370 |
Swimming vs running, cycling and walking
How does a swim stack up against the same time on land? Here are 30 minutes and an hour for a 70 kg person, all from the 2024 Compendium. The calculator runs this comparison for your own weight and minutes under every result.
| Activity | Code | MET | kcal, 30 min | kcal, 60 min |
|---|---|---|---|---|
| Swimming, front crawl steady | 18290 | 8.0 | 295 | 590 |
| Swimming, breaststroke recreational | 18265 | 5.3 | 195 | 390 |
| Swimming, butterfly | 18270 | 13.8 | 505 | 1015 |
| Running, about a 10-minute mile | 12050 | 9.3 | 340 | 685 |
| Cycling, 12 to 13.9 mph | 01030 | 8.0 | 295 | 590 |
| Cycling, 10 to 11.9 mph | 01020 | 6.8 | 250 | 500 |
| Walking, brisk, 3.5 to 3.9 mph | 17200 | 4.8 | 175 | 355 |
| Walking, moderate, 2.8 to 3.4 mph | 17190 | 3.8 | 140 | 280 |
70 kg, kcal rounded to the nearest 5.
Steady front crawl and moderate cycling come out the same (MET 8.0), steady running is a little higher and brisk walking is about half. Gentle breaststroke sits between walking and cycling. The real difference is how long you can keep going: a confident swimmer can often swim for longer than they could run, with far less impact. For running in more detail, including hills, try the running calorie calculator.
Is swimming good for weight loss?
Swimming can help, for a few reasons. It burns a fair amount of energy, especially if you swim continuously. It works your whole body, arms included. It's low impact, so most people can do more of it, more often, than high-impact exercise. And plenty of people simply enjoy it more than the gym, which is what keeps them doing it.
What swimming can't do is override your overall energy balance. If a 30-minute swim costs 295 kcal and is followed by a large hot chocolate and a toastie, the swim hasn't moved the needle. Knowing your number helps you make that call.
Why you might not be losing weight swimming
- Counting the rests. A 45-minute pool session is often far less actual swimming. Only count the time you're moving.
- Swimming very gently. Slow breaststroke with your head up is relaxing, but at MET 5.3 it burns a lot less than steady front crawl.
- Post-swim hunger. Many swimmers feel ravenous afterwards, especially in cooler water, and White and colleagues (2005) found people ate more after cool-water exercise.
- Eating it back. The body-weight equivalent under the result uses the 3,500 kcal per pound rule, which is only a rough guide (Hall, 2008) and assumes none of it is eaten back.
How to burn more calories swimming
- Swim for longer. Time in the water is the biggest lever you have.
- Rest less. Shorter breaks at the wall keep your effort up.
- Add harder sets. Intervals, such as 4 × 50 m quick with a short rest, raise the average effort of a session.
- Mix the strokes. A few lengths of butterfly or hard breaststroke push the number up.
- Work on technique. Smoother swimming lets you keep going for longer, which usually matters more than the stroke.
Want help with that last one? James's free 4-week pool plan at JG Fitness builds a smoother, fitter front crawl.
A swim on an empty stomach suits some people and not others. Read what to eat before swimming, whether you should eat before swimming and how long after eating you can swim.
How the swimming calorie calculator works
What a MET is
A MET (metabolic equivalent) compares an activity's energy cost with sitting still. One MET is about 3.5 ml of oxygen per kg of body weight per minute. As a rough guide, under 3 MET is light activity, 3 to 6 is moderate and over 6 is vigorous. Most proper lane swimming is vigorous; gentle treading water and slow water walking are light to moderate.
Dividing by 200 converts oxygen use to kcal per minute (the standard ACSM equation). Multiply by your minutes for the total, and by 4.184 for kJ.
- 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), 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: type your pace per 100 m and we use the front-crawl band nearest to it.
- Weight: 1 stone = 6.35029 kg and 1 lb = 0.453592 kg. We use your actual weight. Some calculators swap in an “adjusted” weight for people with obesity; the Compendium equation doesn't, so neither do we. Treat the result as an estimate either way.
- Over 60? The 2024 Older Adult Compendium has no swimming entries, so the adult values are used for everyone here. The running calculator does have an over-60 option.
- Land comparison: running at 6 to 6.3 mph (MET 9.3), cycling at 12 to 13.9 mph (8.0) and brisk walking at 3.5 to 3.9 mph (4.8), for the same minutes.
These are gross figures, so they include what you'd burn sitting still. 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 | kcal, 30 min at 70 kg |
|---|---|---|---|
| Front crawl, easy (slow, 30 to 45 yd/min) | 18292 | 5.8 | 215 |
| Front crawl laps, slow recreational | 18240 | 5.8 | 215 |
| Front crawl, steady (medium, ~50 yd/min) | 18290 | 8.0 | 295 |
| Front crawl laps, fast vigorous | 18230 | 9.8 | 360 |
| Front crawl, fast (~75 yd/min) | 18280 | 10.5 | 385 |
| Front crawl, elite competition (over 90 yd/min) | 18294 | 14.5 | 535 |
| Breaststroke, recreational | 18265 | 5.3 | 195 |
| Breaststroke, training or competition | 18260 | 10.3 | 380 |
| Backstroke, recreational | 18255 | 4.8 | 175 |
| Backstroke, training or competition | 18250 | 9.5 | 350 |
| Butterfly, general | 18270 | 13.8 | 505 |
| Sidestroke, general | 18320 | 7.0 | 255 |
| Leisurely, not lap swimming | 18310 | 6.0 | 220 |
| Lake, sea or river | 18300 | 6.0 | 220 |
| Open water, 5k swim | 18285 | 10.5 | 385 |
| Synchronised swimming | 18330 | 8.0 | 295 |
| Treading water, moderate | 18350 | 3.5 | 130 |
| Treading water, fast | 18340 | 9.8 | 360 |
Herrmann SD, Willis EA, Ainsworth BE et al. 2024 Adult Compendium of Physical Activities. Water activities.
What to eat around your swim
Simple, sourced guides from a personal trainer and swim coach. No diets, no fads.
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.
Calories burned swimming FAQ
How many calories does swimming burn in 30 minutes?
For a 70 kg person, about 215 kcal of easy front crawl, 295 kcal steady and 505 kcal of butterfly, using the 2024 Compendium. Recreational breaststroke is about 195. The 30-minute table shows 60 to 100 kg.
How many calories does swimming burn in an hour?
For a 70 kg swimmer, about 425 kcal of easy front crawl, 590 kcal steady and 1015 kcal of butterfly. Rests at the wall bring the real figure down, so only count the minutes you were actually swimming.
Which swimming stroke burns the most calories?
Butterfly has the highest Compendium value of the four main strokes (MET 13.8). Only elite-pace front crawl, over 90 yards a minute, is rated higher (14.5). After butterfly come fast front crawl (10.5 at about 75 yd a minute), hard breaststroke (10.3) and hard backstroke (9.5). Gentle backstroke is the lowest of the four (4.8). In practice, the stroke you can keep going longest often burns the most in a session.
How many calories does one length burn?
About 5 to 8 kcal per 25 m length of steady front crawl for someone weighing 60 to 100 kg, at the Compendium's ~50 yd a minute. Pick “Lengths” in the calculator for your own pool and count.
How many calories does swimming 1 km burn?
For a 70 kg swimmer doing front crawl at the Compendium's paces, about 207 kcal easy, 214 kcal steady and 188 kcal fast. The per-km figure barely changes with speed, because faster swimming finishes sooner. For breaststroke or backstroke, pick “Lengths” and add the time it took.
Is swimming good for weight loss?
It can be. It burns a useful amount, it's gentle on joints and you can do a lot of it without the pounding of running. What decides weight loss is your overall energy balance, so a swim helps most when it isn't followed by a much bigger meal.
Why am I not losing weight swimming?
Common reasons are counting time at the wall as swimming, eating more after cooler sessions (White et al., 2005 found people ate more after exercising in cooler water), swimming too gently to burn much, and simply eating back what you burned. Look at the whole week, not one session.
How can I burn more calories swimming?
Swim for longer, cut the rests, and add harder sets such as fast front-crawl intervals or a few lengths of butterfly or hard breaststroke. Better technique also lets you swim more continuously, which often matters more than the stroke itself.
How many calories does water aerobics burn?
The Compendium rates general water aerobics at MET 5.5, about 305 kcal in a 45-minute class for a 70 kg person. High-intensity classes are rated 7.5 (about 415 kcal) and resistance-based ones 3.8.
Is swimming or running better for burning calories?
Minute for minute, steady running (about a 10-minute mile, MET 9.3) burns a bit more than steady front crawl (8.0): for a 70 kg person over 30 minutes that's about 340 vs 295 kcal. Hard swimming beats easy running, though, and many people can swim for longer than they can run.
Does swimming in cold water burn more calories?
The Compendium has no separate cold-water value, so the calculator doesn't add anything. One study (White et al., 2005) found similar energy use exercising in 20°C and 33°C water, but people ate 44% more afterwards when the water was cooler.
Is the swimming calorie calculator accurate?
It uses published averages, so it's an estimate, not a measurement. Technique makes a big difference in the water: a skilled swimmer covers more distance for the same effort. Use it to compare sessions and plan food, not to count every calorie.
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 2 Nov 2026. pacompendium.com/water-activities
- 2024 Adult Compendium, Running (codes 12xxx), opened 2 Nov 2026. pacompendium.com/running
- 2024 Adult Compendium, Bicycling (codes 01xxx), opened 2 Nov 2026. pacompendium.com/bicycling
- 2024 Adult Compendium, Walking (codes 17xxx), opened 2 Nov 2026. pacompendium.com/walking
- 2024 Older Adult Compendium of Physical Activities (MET 60+, 2.7 ml/kg/min baseline), opened 2 Nov 2026. pacompendium.com/older-adult-compendium
- 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
- Hall KD. What is the required energy deficit per unit weight loss? International Journal of Obesity 2008;32:573-576. pubmed.ncbi.nlm.nih.gov/17848938