How to Choose the Right Size Swim Nappy

Getting the right size swim nappy makes all the difference between a fun pool day and a stressful one. Too big and you'll have gaps (and potential leaks). Too small and your bub will be uncomfortable. Here's how to nail it.

How Swim Nappy Sizing Works

Unlike regular nappies that go by weight, reusable swim nappies are sized by age and waist/thigh measurements. That's because a swim nappy's job isn't to absorb liquid (water would make it balloon up), it's to contain solids. So the fit around the waist and thighs is what matters most.

Our Size Guide

  • Small (0-6 months): For newborns and small babies. Snug fit around tiny thighs.
  • Medium (6-12 months): The most popular size for babies starting swim lessons.
  • Large (1-2 years): For active toddlers who are on the move.
  • XL (2-3 years): For bigger toddlers still in nappies or as a backup for toilet-training swimmers.

Tips for Getting the Right Fit

Check the thighs. The elastic around the thigh should sit snugly without digging in. You should be able to fit one finger between the elastic and their skin.

Check the waist. Same rule - snug but not tight. The waistband should sit flat without rolling.

Between sizes? Size up. A slightly bigger nappy is always better than one that's too tight. It'll be more comfortable and still do its job.

Try before you swim. Put the nappy on at home first and check the fit before you get to the pool. Way easier to swap sizes on the couch than on a wet change table.

How Many Do You Need?

We recommend at least 2-3 swim nappies if you're swimming regularly. One to wear, one drying, one in the wash. If you swim weekly, you'll get plenty of wear out of each one - our recycled nylon fabric is built to last season after season.

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