Diaper Size Guide: How to Know When It's Time to Size Up

Babies grow fast, and diapers don't always keep up. The right size is the difference between a dry night and a 3 a.m. outfit change. Here's how to tell when it's time to move up, and how to pick between tape diapers and pull-ups.

Signs the diaper is too small

• Red marks around the thighs or waist
• Leaks up the back, especially after a dirty diaper
• The tabs barely reach the front panel
• The top of the diaper sits well below the belly button
• Overnight leaks start happening when they never did before

Signs it's too big

• Gaps around the legs
• Leaks out of the leg openings
• The tabs overlap or reach past the centre

If you're between sizes, most parents find the bigger size works better, especially at night.

Tape diapers or pull-ups?

Tape diapers are easiest for newborns and young babies who change lying down. Once your baby rolls, crawls or wants to stand for changes, pull-ups make life much easier. They go on like underwear, and tear-away sides make cleanup quick.

Our size chart

Sizes aren't the same across brands. A Chiaus L and a Bc Babycare L may fit differently, so go by your baby's weight, not the letter. Not sure? Chiaus pull-ups come in a 4-piece travel pack, so you can try a size before buying a full bag.

Nights need extra help

If daytime fit is fine but nights still leak, try an overnight pant like Pampers Nighttime Pants, which are built to absorb more over a long sleep.

A note on skin

A diaper that's too tight rubs and traps moisture, which is one of the common causes of diaper rash. Read our guide to preventing diaper rash for more.

Still unsure which size to order? Message us on Instagram or WeChat (AladdinKids), or email nihao@aladdinkids.ca. We're parents too, and we're happy to help.