Please see each product page, for individual sizing.

As a general rule, please choose the same size for our period undies and period swimwear as your child's regular underwear size.

Our period underwear is designed here using Australian Child/Youth underwear guidelines. It's important to note that child sizing, also crosses over into women's sizing at our 12/14, so we have also shown this on our sizing charts (on each individual product page) to assist.

We also understand purchasing online can make judging sizing difficult and everyone has a different body shape (literally hundreds of waist & hip combinations) so we have created guides on each product page to help you choose the best fit for each product, or feel free to email our helpful team at theteam@knicked.com.au with waist & hip measurements so we can assist further.

To measure against existing underwear: use the flat lay measurement (side seam to side seam on the waistband) to compare with their current underwear.

Don't panic if you do find you've ordered the wrong size, KNICKED will happily exchange sizing and also cover the postal costs to reship (once per order) as long as underwear has been tried on over clean underwear and returned in AS NEW condition (not washed/worn free of lint/hair/marks), and packaging in original condition.

Please click here for our Exchange/Refund Forms & Guidelines to organise an exchange.