Brand vs brand

Wonder Nation vs Nike sizes

Of Wonder Nation's 11 baby and toddler sizes, 2 line up closely with a Nike size, 7 are partial matches, and 2 have no clean match. Both charts list weight and height, so the comparison uses both.

Closest pairs: Wonder Nation 18M = Nike 12M, Wonder Nation 4T = Nike 4T.

Watch the labels: Wonder Nation 12M is closer to Nike 9M than to Nike's own 12M; Wonder Nation 18M is closer to Nike 12M than to Nike's own 18M; Wonder Nation 24M is closer to Nike 18M than to Nike's own 24M.

Wonder Nation Runs smallNike Runs large

Based on published size charts compared with other brands.

Size by size, on one scale

Each block is one size, placed where the brand's chart puts it. Blocks that sit above each other fit the same baby.

Weight (lb)

Wonder Nation

Preemie: up to 5 lb
Newborn: 5.5 to 7.5 lb
0-3M: 6.5 to 12 lb
3-6M: 12.5 to 16 lb
6-9M: 16.5 to 19 lb
12M: 19.5 to 22 lb
18M: 22.5 to 26 lb
24M: 26.5 to 30 lb
2T: 26.5 to 30 lb
3T: 30.5 to 34 lb
4T: 34.5 to 38 lb

Nike

Newborn/0-3M: 6 to 9.5 lb
3M: 9.9 to 14.6 lb
6M: 15 to 17.9 lb
9M: 18.3 to 22 lb
12M: 22.5 to 24.9 lb
18M: 25.6 to 28 lb
24M: 28.4 to 30 lb
2T: 28.4 to 30 lb
3T: 30.4 to 33.1 lb
4T: 34 to 37.9 lb

Height (in)

Wonder Nation

Preemie: up to 17 in
Newborn: 17.5 to 21 in
0-3M: 20.5 to 23 in
3-6M: 23.5 to 26 in
6-9M: 26.5 to 27.5 in
12M: 28 to 29.5 in
18M: 30 to 31.5 in
24M: 32 to 33.5 in
2T: 32 to 33.5 in
3T: 34 to 37.5 in
4T: 38 to 41.5 in

Nike

Newborn/0-3M: 19.7 to 22 in
3M: 22 to 24.4 in
6M: 24.4 to 26.8 in
9M: 26.8 to 29.1 in
12M: 29.1 to 31.5 in
18M: 31.5 to 33.9 in
24M: 33.9 to 36.2 in
2T: 33.9 to 36.2 in
3T: 36.2 to 38.6 in
4T: 38.6 to 40.9 in

Wonder Nation size to Nike size

Wonder Nation	Closest Nike	Match	Weight: Wonder Nation / Nike	Height: Wonder Nation / Nike
Preemie	None	No clean match	up to 5 lb / n/a	up to 17 in / n/a
Newborn	Newborn/0-3M	Partial	5.5 to 7.5 lb / 6 to 9.5 lb	17.5 to 21 in / 19.7 to 22 in
0-3M	Newborn/0-3M	Partial	6.5 to 12 lb / 6 to 9.5 lb	20.5 to 23 in / 19.7 to 22 in
3-6M	6M	Partial	12.5 to 16 lb / 15 to 17.9 lb	23.5 to 26 in / 24.4 to 26.8 in
6-9M	6M	No clean match	16.5 to 19 lb / 15 to 17.9 lb	26.5 to 27.5 in / 24.4 to 26.8 in
12M	9M	Partial	19.5 to 22 lb / 18.3 to 22 lb	28 to 29.5 in / 26.8 to 29.1 in
18M	12M	Close match	22.5 to 26 lb / 22.5 to 24.9 lb	30 to 31.5 in / 29.1 to 31.5 in
24M	18M	Partial	26.5 to 30 lb / 25.6 to 28 lb	32 to 33.5 in / 31.5 to 33.9 in
2T	18M	Partial	26.5 to 30 lb / 25.6 to 28 lb	32 to 33.5 in / 31.5 to 33.9 in
3T	3T	Partial	30.5 to 34 lb / 30.4 to 33.1 lb	34 to 37.5 in / 36.2 to 38.6 in
4T	4T	Close match	34.5 to 38 lb / 34 to 37.9 lb	38 to 41.5 in / 38.6 to 40.9 in

Nike size to Wonder Nation size

Nike	Closest Wonder Nation	Match	Weight: Nike / Wonder Nation	Height: Nike / Wonder Nation
Newborn/0-3M	0-3M	Partial	6 to 9.5 lb / 6.5 to 12 lb	19.7 to 22 in / 20.5 to 23 in
3M	3-6M	Partial	9.9 to 14.6 lb / 12.5 to 16 lb	22 to 24.4 in / 23.5 to 26 in
6M	3-6M	Partial	15 to 17.9 lb / 12.5 to 16 lb	24.4 to 26.8 in / 23.5 to 26 in
9M	12M	Partial	18.3 to 22 lb / 19.5 to 22 lb	26.8 to 29.1 in / 28 to 29.5 in
12M	18M	Close match	22.5 to 24.9 lb / 22.5 to 26 lb	29.1 to 31.5 in / 30 to 31.5 in
18M	24M	Partial	25.6 to 28 lb / 26.5 to 30 lb	31.5 to 33.9 in / 32 to 33.5 in
24M	3T	Partial	28.4 to 30 lb / 30.5 to 34 lb	33.9 to 36.2 in / 34 to 37.5 in
2T	3T	Partial	28.4 to 30 lb / 30.5 to 34 lb	33.9 to 36.2 in / 34 to 37.5 in
3T	3T	Partial	30.4 to 33.1 lb / 30.5 to 34 lb	36.2 to 38.6 in / 34 to 37.5 in
4T	4T	Close match	34 to 37.9 lb / 34.5 to 38 lb	38.6 to 40.9 in / 38 to 41.5 in

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Every Wonder Nation size in Nike

Close match

Wonder Nation 18M lines up closely with Nike 12M.

Weight (lb)

Wonder Nation 18M 22.5 to 26 lb

Nike 12M 22.5 to 24.9 lb

Nike 18M 25.6 to 28 lb

Height (in)

Wonder Nation 18M 30 to 31.5 in

Nike 12M 29.1 to 31.5 in

Nike 18M 31.5 to 33.9 in

The shaded column is the Wonder Nation range. Bars show what each brand publishes for the size.

Based on published size charts. Wonder Nation chart and Nike chart.

More comparisons

Charts retrieved October 4, 2026 (Wonder Nation) and October 4, 2026 (Nike). Sources are listed on each brand page. This site is not affiliated with either brand.