Sizing guide — kinder vs primary backpacks

The most common question parents ask: do I buy the toddler/kinder backpack now and re-buy at primary, or buy a primary backpack early and let them grow into it? The honest answer is: don't size up. Buy the size that fits now. Here's why, with the actual measurements.

Backpack proportions, by stage

Toddler backpack (1-3 years)

  • Small: 32 × 25 × 12 cm
  • Regular: 39 × 29 × 13 cm
  • Best for: 1-3 year olds, especially first daycare

Kinder backpack (3-5 years)

  • Slightly larger, holds a library book + lunch box + spare clothes
  • Best for: 3-5 year olds at kinder

Primary backpack (5-8 years)

  • Structured shape, padded straps, separate compartments for lunch + library + supplies
  • Holds A4 readers, hardback library books
  • Best for: 5-8 year olds, full primary school day

Why not size up?

An oversized backpack is the leading cause of school-age back pain in Australian children (RCH Melbourne research, 2023). A child carrying a backpack that's more than 10% of their body weight develops postural compensation that's hard to reverse. The bag should sit between the shoulders and the hip bones, never below.

A kinder-sized 4-year-old in a primary-sized backpack carries it lower because it's too big — exactly the wrong position. Buy the size that fits now. Re-buy when they grow into the next stage.

The rule of thumb

If you have to ask whether to size up, don't size up. Welcomenest backpacks are made to last past one child, so the kinder bag you buy today can pass to a sibling, or go to the comforter cupboard as a keepsake when the child outgrows it. The cost-per-year is lower than a bag that doesn't fit properly for two years and then gets discarded.

Browse the right size

Free shipping over $75 Australia-wide. Hand-embroidered with your child's name in our Melbourne studio. Made-to-order in five to seven days.

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