Brand vs brand

Old Navy vs Little Sleepies sizes

Of Old Navy's 10 baby and toddler sizes, 2 line up closely with a Little Sleepies size, 8 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 = Little Sleepies 3-6M, Old Navy 3T = Little Sleepies 3T.

Watch the labels: Old Navy 0-3M is closer to Little Sleepies 0-3M than to Little Sleepies' own 0-3M; Old Navy 3-6M is closer to Little Sleepies 3-6M than to Little Sleepies' own 3-6M; Old Navy 6-12M is closer to Little Sleepies 6-12M than to Little Sleepies' own 6-12M.

Old Navy True to sizeLittle Sleepies True to size

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

Little Sleepies

Preemie: up to 5 lb
Newborn: 5 to 8 lb
0-3M: 8 to 12 lb
3-6M: 12 to 17 lb
6-12M: 17 to 23 lb
12-18M: 23 to 26 lb
18-24M: 26 to 30 lb
2T: 29 to 31 lb
3T: 31 to 35 lb
4T: 35 to 39 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

Little Sleepies

Preemie: up to 18 in
Newborn: 18 to 21 in
0-3M: 21 to 23 in
3-6M: 23 to 27 in
6-12M: 27 to 31 in
12-18M: 31 to 33 in
18-24M: 33 to 34.5 in
2T: 33 to 36 in
3T: 36 to 39 in
4T: 39 to 42 in

Old Navy size to Little Sleepies size

Old Navy	Closest Little Sleepies	Match	Weight: Old Navy / Little Sleepies	Height: Old Navy / Little Sleepies
Up to 7 lb	Newborn	Partial	up to 6.6 lb / 5 to 8 lb	up to 21.7 in / 18 to 21 in
0-3M	0-3M	Partial	6.6 to 13.2 lb / 8 to 12 lb	21.7 to 24 in / 21 to 23 in
3-6M	3-6M	Close match	13.2 to 17.6 lb / 12 to 17 lb	24 to 26.4 in / 23 to 27 in
6-9M	6-12M	Partial	17.6 to 19.8 lb / 17 to 23 lb	26.4 to 29.1 in / 27 to 31 in
6-12M	6-12M	Partial	17.6 to 22 lb / 17 to 23 lb	26.4 to 29.1 in / 27 to 31 in
12-18M	6-12M	Partial	22 to 24.3 lb / 17 to 23 lb	29.1 to 31.5 in / 27 to 31 in
18-24M	12-18M	Partial	24.3 to 26.5 lb / 23 to 26 lb	31.5 to 33.9 in / 31 to 33 in
2T	18-24M	Partial	26.5 to 28.7 lb / 26 to 30 lb	33.9 to 36.2 in / 33 to 34.5 in
3T	3T	Close match	28.7 to 33.1 lb / 31 to 35 lb	36.2 to 39 in / 36 to 39 in
4T	4T	Partial	33.1 to 35.3 lb / 35 to 39 lb	39 to 42.1 in / 39 to 42 in

Little Sleepies size to Old Navy size

Little Sleepies	Closest Old Navy	Match	Weight: Little Sleepies / Old Navy	Height: Little Sleepies / Old Navy
Preemie	Up to 7 lb	No clean match	up to 5 lb / up to 6.6 lb	up to 18 in / up to 21.7 in
Newborn	Up to 7 lb	Partial	5 to 8 lb / up to 6.6 lb	18 to 21 in / up to 21.7 in
0-3M	0-3M	Partial	8 to 12 lb / 6.6 to 13.2 lb	21 to 23 in / 21.7 to 24 in
3-6M	3-6M	Close match	12 to 17 lb / 13.2 to 17.6 lb	23 to 27 in / 24 to 26.4 in
6-12M	6-12M	Partial	17 to 23 lb / 17.6 to 22 lb	27 to 31 in / 26.4 to 29.1 in
12-18M	18-24M	Partial	23 to 26 lb / 24.3 to 26.5 lb	31 to 33 in / 31.5 to 33.9 in
18-24M	2T	Partial	26 to 30 lb / 26.5 to 28.7 lb	33 to 34.5 in / 33.9 to 36.2 in
2T	2T	Partial	29 to 31 lb / 26.5 to 28.7 lb	33 to 36 in / 33.9 to 36.2 in
3T	3T	Close match	31 to 35 lb / 28.7 to 33.1 lb	36 to 39 in / 36.2 to 39 in
4T	4T	Partial	35 to 39 lb / 33.1 to 35.3 lb	39 to 42 in / 39 to 42.1 in

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Size

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Every Old Navy size in Little Sleepies

Close match

Old Navy 3-6M lines up closely with Little Sleepies 3-6M.

Weight (lb)

Old Navy 3-6M 13.2 to 17.6 lb

Little Sleepies 3-6M 12 to 17 lb

Little Sleepies 6-12M 17 to 23 lb

Height (in)

Old Navy 3-6M 24 to 26.4 in

Little Sleepies 3-6M 23 to 27 in

Little Sleepies 6-12M 27 to 31 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 Little Sleepies chart.

More comparisons

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