Brand vs brand

Old Navy vs Nike sizes

Of Old Navy's 10 baby and toddler sizes, 6 line up closely with a Nike size, 4 are partial matches, and 0 have no clean match. Both charts list weight and height, so the comparison uses both.

Closest pairs: Old Navy 3-6M = Nike 6M, Old Navy 6-9M = Nike 9M, Old Navy 6-12M = Nike 9M, Old Navy 12-18M = Nike 12M.

Watch the labels: Old Navy 2T is closer to Nike 24M than to Nike's own 2T.

Old Navy True to sizeNike 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)

Old Navy

Up to 7 lb: up to 6.6 lb
0-3M: 6.6 to 13.2 lb
3-6M: 13.2 to 17.6 lb
6-9M: 17.6 to 19.8 lb
6-12M: 17.6 to 22 lb
12-18M: 22 to 24.3 lb
18-24M: 24.3 to 26.5 lb
2T: 26.5 to 28.7 lb
3T: 28.7 to 33.1 lb
4T: 33.1 to 35.3 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)

Old Navy

Up to 7 lb: up to 21.7 in
0-3M: 21.7 to 24 in
3-6M: 24 to 26.4 in
6-9M: 26.4 to 29.1 in
6-12M: 26.4 to 29.1 in
12-18M: 29.1 to 31.5 in
18-24M: 31.5 to 33.9 in
2T: 33.9 to 36.2 in
3T: 36.2 to 39 in
4T: 39 to 42.1 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

Old Navy size to Nike size

Old Navy	Closest Nike	Match	Weight: Old Navy / Nike	Height: Old Navy / Nike
Up to 7 lb	Newborn/0-3M	Partial	up to 6.6 lb / 6 to 9.5 lb	up to 21.7 in / 19.7 to 22 in
0-3M	3M	Partial	6.6 to 13.2 lb / 9.9 to 14.6 lb	21.7 to 24 in / 22 to 24.4 in
3-6M	6M	Close match	13.2 to 17.6 lb / 15 to 17.9 lb	24 to 26.4 in / 24.4 to 26.8 in
6-9M	9M	Close match	17.6 to 19.8 lb / 18.3 to 22 lb	26.4 to 29.1 in / 26.8 to 29.1 in
6-12M	9M	Close match	17.6 to 22 lb / 18.3 to 22 lb	26.4 to 29.1 in / 26.8 to 29.1 in
12-18M	12M	Close match	22 to 24.3 lb / 22.5 to 24.9 lb	29.1 to 31.5 in / 29.1 to 31.5 in
18-24M	18M	Close match	24.3 to 26.5 lb / 25.6 to 28 lb	31.5 to 33.9 in / 31.5 to 33.9 in
2T	24M	Partial	26.5 to 28.7 lb / 28.4 to 30 lb	33.9 to 36.2 in / 33.9 to 36.2 in
3T	3T	Close match	28.7 to 33.1 lb / 30.4 to 33.1 lb	36.2 to 39 in / 36.2 to 38.6 in
4T	4T	Partial	33.1 to 35.3 lb / 34 to 37.9 lb	39 to 42.1 in / 38.6 to 40.9 in

Nike size to Old Navy size

Nike	Closest Old Navy	Match	Weight: Nike / Old Navy	Height: Nike / Old Navy
Newborn/0-3M	Up to 7 lb	Partial	6 to 9.5 lb / up to 6.6 lb	19.7 to 22 in / up to 21.7 in
3M	0-3M	Partial	9.9 to 14.6 lb / 6.6 to 13.2 lb	22 to 24.4 in / 21.7 to 24 in
6M	3-6M	Close match	15 to 17.9 lb / 13.2 to 17.6 lb	24.4 to 26.8 in / 24 to 26.4 in
9M	6-12M	Close match	18.3 to 22 lb / 17.6 to 22 lb	26.8 to 29.1 in / 26.4 to 29.1 in
12M	12-18M	Close match	22.5 to 24.9 lb / 22 to 24.3 lb	29.1 to 31.5 in / 29.1 to 31.5 in
18M	18-24M	Close match	25.6 to 28 lb / 24.3 to 26.5 lb	31.5 to 33.9 in / 31.5 to 33.9 in
24M	2T	Partial	28.4 to 30 lb / 26.5 to 28.7 lb	33.9 to 36.2 in / 33.9 to 36.2 in
2T	2T	Partial	28.4 to 30 lb / 26.5 to 28.7 lb	33.9 to 36.2 in / 33.9 to 36.2 in
3T	3T	Close match	30.4 to 33.1 lb / 28.7 to 33.1 lb	36.2 to 38.6 in / 36.2 to 39 in
4T	4T	Partial	34 to 37.9 lb / 33.1 to 35.3 lb	38.6 to 40.9 in / 39 to 42.1 in

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Size

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Every Old Navy size in Nike

Close match

Old Navy 3-6M lines up closely with Nike 6M.

Weight (lb)

Old Navy 3-6M 13.2 to 17.6 lb

Nike 3M 9.9 to 14.6 lb

Nike 6M 15 to 17.9 lb

Height (in)

Old Navy 3-6M 24 to 26.4 in

Nike 3M 22 to 24.4 in

Nike 6M 24.4 to 26.8 in

The shaded column is the Old Navy range. Bars show what each brand publishes for the size.

Based on published size charts. Old Navy chart and Nike chart.

More comparisons

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