Swimming Calorie Calculator
A 155 lb person swimming moderate freestyle for 30 minutes burns about 214 calories, and the same half hour of butterfly burns around 509. This swimming calorie calculator estimates your burn from body weight, time in the water, and stroke, using MET values from the Compendium of Physical Activities. Stroke choice changes the answer more than almost anything else.
Quick answer
Calories depend on your weight, how long you swim, and how demanding the stroke is.
Calories burned
214 calories
Calories per hour
428
MET value
5.8
What this tells you
- •Calories depend on your weight, how long you swim, and how demanding the stroke is.
- •Each stroke has a MET value, from 3.5 for treading water up to 13.8 for butterfly.
- •The formula is calories per minute = MET x 3.5 x weight in kg / 200.
- •Vigorous freestyle burns nearly 70 percent more than easy freestyle, so effort level matters as much as stroke.
How to Use
- 1Enter your body weight in pounds or kilograms.
- 2Enter your time actually swimming, not total pool time.
- 3Pick the stroke and effort that best matches your session.
- 4Read the total calories and the hourly burn rate.
How It Works
Formula
calories per minute = MET x 3.5 x weight (kg) / 200MET values measure how many times harder an activity works than sitting still. Moderate freestyle is 5.8 METs, so a 70.3 kg (155 lb) swimmer burns 5.8 x 3.5 x 70.3 / 200, about 7.1 calories a minute, or 214 in half an hour. Butterfly at 13.8 METs burns 17 calories a minute, which is why nobody swims it for long.
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
30 minutes of moderate freestyle, 155 lb
5.8 METs at 70.3 kg burns roughly 7.1 calories a minute.
45 minutes of breaststroke, 80 kg
Breaststroke at 5.3 METs burns about 7.4 calories a minute at 80 kg.
20 minutes of vigorous freestyle, 180 lb
Hard lap swimming at 9.8 METs burns about 14 calories a minute at 81.6 kg.
Calories per 30 Minutes by Stroke (155 lb swimmer)
Estimated burn for a 155 lb (70.3 kg) person swimming 30 minutes.
| Stroke | MET | Calories in 30 min |
|---|---|---|
| Treading water, moderate | 3.5 | 129 |
| Backstroke | 4.8 | 177 |
| Breaststroke | 5.3 | 196 |
| Freestyle, moderate | 5.8 | 214 |
| Leisurely (general) | 6.0 | 221 |
| Freestyle, vigorous | 9.8 | 362 |
| Butterfly | 13.8 | 509 |
Common mistakes
- Counting total pool time. Rest at the wall between laps burns far less, so enter actual swimming minutes.
- Assuming swimming always beats running. Easy swimming burns about like brisk walking. The water hides how easy or hard you are working.
- Ignoring effort level within a stroke. Vigorous freestyle burns nearly 70 percent more than a gentle cruise.