One reader found this site by searching Yahoo for how far is a swimming lap. There are a few different ways to determine the distance from one end of the pool to another, which will gives you the length of the pool. Multiply the length by two and you will have the distance of a lap in the pool. Most pools that you are likely to swim laps in are going to be either 25 yards (75 feet) or 25 meters (82+ feet). Here are some common ways of measuring a pool:

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  Photo by Dawn PerryAsk the lifeguard. The easiest way to determine the size of a swimming pool is just to ask somebody at the pool who knows.
• Check the pool for markings. Most pools will mark the pool at regular intervals along the edges. Just be careful not to confuse distance markers with depth markers.
• Mark a rope. You could use floating lane dividers for this purpose if you are not worried about being precise, but if you mark a rope at regular intervals and then attach the ends of the rope to the edges of the pool, you can easily determine the length. The easiest method is for one person to hold the end of the rope at one edge, and for a second person to carry the rope to the far edge and pull it taught to mark where the pool edge lies. Check the marks on the rope to determine the length. A long tape measure could also be used along the edge of the pool.
• Determine the circumference of a round pool. If you are not swimming in a standard Olympic sized swimming pool, but are in an oddly shaped or round pool, then you need to determine how you will be swimming your laps and measure accordingly. If you are going to swim along the outside edge of an above ground pool, then determine the approximate circumference by determining the diameter and multiplying it by 3. The diameter is the distance from one edge of the pool to the other while passing through the center of the pool. The actual circumference would be measured by multiplying by Pi, a mathematical constant that is approximately 3.14. The distance that you swim will be less than the circumference of the pool, however, as you will not be swimming through the outside edge and will be to the inside a bit. Multiplying by 3 will still give you a long estimate, but makes the math easier. Placing a rope in the pool is probably an easier way to measure, and bound to be more accurate. You will need some way of keeping the rope floating through your approximate swim path.