Swimming Calories Burned Calculator (By Stroke)
Calculate calories burned swimming by stroke type, intensity, and duration, and compare strokes for your workout.
Reviewed by Sher, Sports Science & Nutrition Specialist
Formula
Calories = (MET x 3.5 x Weight_kg) / 200 x Duration_min
Where MET is the Metabolic Equivalent of Task specific to each swimming stroke and intensity level (ranging from 3.5 for light treading to 13.8 for vigorous butterfly), Weight is body mass in kilograms, and Duration is swim time in minutes.
Worked Examples
Example 1: Morning Freestyle Workout
Problem:A 70 kg swimmer does 30 minutes of moderate freestyle. How many calories are burned and approximately how many laps?
Solution:MET for moderate freestyle = 7.0\nCalories per minute = (7.0 x 3.5 x 70) / 200 = 8.575 cal/min\nTotal calories = 8.575 x 30 = 257.25 calories\nSeconds per lap (25m pool, moderate) = 22 seconds\nTotal laps = (30 x 60) / 22 = 81 laps\nTotal distance = 81 x 25 = 2,025 meters
Result:257 calories burned | 81 laps | 2,025 meters in 30 minutes of moderate freestyle
Example 2: Vigorous Butterfly Session
Problem:An 85 kg competitive swimmer does 20 minutes of vigorous butterfly. Calculate calorie burn.
Solution:MET for vigorous butterfly = 13.8\nCalories per minute = (13.8 x 3.5 x 85) / 200 = 20.53 cal/min\nTotal calories = 20.53 x 20 = 410.6 calories\nSeconds per lap (25m pool, vigorous) = 18 seconds\nTotal laps = (20 x 60) / 18 = 66 laps\nTotal distance = 66 x 25 = 1,650 meters
Result:411 calories burned | 66 laps | 1,650 meters in 20 minutes of vigorous butterfly
Frequently Asked Questions
How many calories does swimming burn per hour?
Swimming burns between 400 and 900 calories per hour depending on the stroke, intensity, and your body weight. Butterfly stroke at a vigorous pace is the most calorie-intensive, burning up to 900 calories per hour for a 70-kilogram person, while leisurely sidestroke might burn around 300 to 400 calories. Freestyle at a moderate pace, the most common swimming workout, typically burns about 500 to 600 calories per hour. Swimming burns more calories than many land-based exercises because water is roughly 800 times denser than air, creating constant resistance against every movement. Additionally, your body expends extra energy maintaining core temperature in water that is cooler than body temperature, adding to the total calorie expenditure during your swim.
Which swimming stroke burns the most calories?
Butterfly stroke is by far the highest calorie-burning swimming stroke, with a MET value of 11.0 to 13.8 depending on intensity. This makes it comparable to running at a fast pace. Butterfly requires powerful simultaneous arm movements and an undulating body motion that engages the core, shoulders, back, chest, and legs all at once. However, butterfly is extremely demanding and most swimmers cannot sustain it for long periods. For sustained swimming workouts, breaststroke at vigorous intensity (MET 10.3) is the next highest calorie burner and is more sustainable for longer sessions. Freestyle (front crawl) offers the best balance of calorie burn and sustainability for most swimmers, with moderate freestyle burning about 500 to 600 calories per hour for an average adult.
Is swimming good for weight loss compared to running?
Swimming is an excellent exercise for weight loss that offers comparable calorie burn to running with significantly less impact on joints. Vigorous freestyle swimming burns approximately 600 to 800 calories per hour, similar to running at 5 to 6 miles per hour. The major advantage of swimming for weight loss is its low-impact nature, which allows people with joint problems, obesity, or injuries to exercise intensely without pain. The water provides buoyancy that supports your body weight, reducing stress on knees, hips, and ankles by up to 90 percent. However, some studies suggest that swimming may be slightly less effective for weight loss than land exercises because cold water exposure can increase appetite. To counter this effect, plan your post-swim meals in advance and focus on protein-rich foods that promote satiety.
How does water temperature affect calories burned while swimming?
Water temperature has a notable effect on calorie expenditure during swimming, though the relationship is complex. Swimming in cooler water (below 25 degrees Celsius or 77 degrees Fahrenheit) forces your body to generate additional heat to maintain its core temperature of 37 degrees Celsius, which burns extra calories. However, extremely cold water can cause muscles to stiffen and reduce swimming efficiency, potentially shortening your workout. Pool temperatures between 25 and 28 degrees Celsius are generally considered optimal for lap swimming, warm enough for comfort but cool enough to provide some thermoregulatory calorie benefit. Open water swimming in colder conditions can burn 10 to 20 percent more calories than pool swimming at the same intensity. Water that is too warm (above 30 degrees Celsius) can cause overheating during vigorous exercise.
References
Reviewed by Sher, Sports Science & Nutrition Specialist · Editorial policy