Swimming Lengths Calculator
Enter the pool length and a distance to see the lengths, or enter lengths to see the distance. Add a time to see your pace.
A length is one trip from one end to the other. A lap is a length there and a length back.
Worked examples
A 1500 metre swim
25 metre pool, 1500 metres, 30:00
60 lengths, 2:00 per 100 metres
30 seconds a length.
About Swimming Lengths Calculator
Swimming sets are written in distances, but you count lengths. This calculator turns one into the other for any pool, in metres or in yards. In a 25 metre pool, 400 metres is 16 lengths, 800 is 32 and 1500 is 60. In a 25 yard pool, a mile takes about 70 lengths. A length is one trip from one end of the pool to the other, and a lap is a length there and a length back.
Add your time and the calculator also works out your pace for each 100, the time for each length and your speed. Or work the other way: enter the pace you want to hold and see how long the whole distance will take. If your target is not a whole number of lengths, the page tells you the closest whole number and the distance that covers, which saves counting mistakes in the water.
How to use Swimming Lengths Calculator
- Choose the pool length and whether you measure in metres or yards.
- Choose whether you know the distance or the number of lengths.
- Enter the distance or the lengths.
- Add your time, or a pace for each 100, to see your pace or the finishing time.
Common uses
- Planning a swim session in a leisure centre pool
- Converting a triathlon swim distance to lengths
- Working out pace for a charity swim
- Tracking progress by pace for each 100
Frequently asked questions
How many lengths is 1500 metres?
60 lengths in a 25 metre pool, 30 in a 50 metre pool.
What is the difference between a length and a lap?
A length is one way across the pool. A lap is usually taken to be there and back, so two lengths. Check which is meant, as pools and clubs differ.
How many lengths is a mile?
A mile is 1609.3 metres, which is 64.4 lengths of a 25 metre pool, or 70.4 lengths of a 25 yard pool.
How is pace for each 100 worked out?
Your total time divided by the distance, multiplied by 100. 1500 metres in 30 minutes is 2 minutes for each 100 metres.
Can I enter a time in hours?
Yes. Write h:mm:ss, for example 1:02:05. A plain number counts as minutes.