Old Navy
Here’s how Old Navy fits your child compared to other brands you might be considering, so you know before it’s in your cart.
Find your child’s size in Old Navy
Enter your child’s measurements once — we’ll size them in Old Navy and at 100+ other brands, each from that brand’s own published chart. Height and weight are required; add chest, waist, hips and inseam to sharpen the fit.
Your child wears one size in Old Navy. What should you buy elsewhere?
Pick the size your child wears at Old Navy to see which brands have the same label and measurements (twins) and which run shorter or longer (strangers) — based on each brand’s own chart.
Show the full cross-brand table (every size)
| Old Navy | Size twinssame number fits the same | Size strangerssame number, different cut |
|---|---|---|
| Up to 7 lbs0–21.5" | — | Gymboree↓ shorter |
| 0-3M21.5–24" | ||
| 3-6M24–26.5" | None — consistent across brands | |
| 6-12M26.5–29" | Patagonia Kids↑ longer | |
| 6-9M26.5–29" | None — consistent across brands | |
| 12-18M29–31.5" | ||
| 18-24M31.5–33.8" | Columbia Kids↑ longerHanna Andersson↓ shorter | |
| 2T33.8–36" | Garanimals↓ shorterMacy's Epic Threads↓ shorterMacy's First Impressions↓ shorterThe Children's Place↓ shorterWalmart Wonder Nation↓ shorterGerber Childrenswear↓ shorter+1 more | |
| 3T36–39" | Garanimals↓ shorterMacy's Epic Threads↓ shorterMacy's First Impressions↓ shorterWalmart Wonder Nation↓ shorter | |
| 4T39–42" | ||
| 5T42–45" | ||
| 542–45" | Il Gufo↓ shorter | |
| 6T45–47" | None — consistent across brands | |
| 645–49" | Bonpoint↓ shorterIl Gufo↓ shorterConverse Kids↓ shorterU.S. Polo Assn.↓ shorterMini Mioche↓ shorterLevi's Kids↓ shorter+8 more | |
| 747.5–50" | Converse Kids↓ shorterGarnet Hill↑ longerPolo Ralph Lauren Kids↑ longerReebok Kids↑ longerEddie Bauer↑ longerFabletics↑ longer+6 more | |
| 853–55" | Il Gufo↓ shorterBonpoint↓ shorterU.S. Polo Assn.↓ shorterNext Kids↓ shorterMini Mioche↓ shorterJacadi↓ shorter+29 more | |
| 1055–57" | Il Gufo↓ shorterBonpoint↓ shorterGymboree↓ shorterHudson Baby↓ shorterTea Collection↓ shorterThe Children's Place↓ shorter+12 more | |
| 1257–60" | Noralee↑ longerU.S. Polo Assn.↓ shorterRylee + Cru↑ longerIl Gufo↓ shorterColumbia Kids↓ shorterGuess↓ shorter+9 more | |
| 1460–62" | Petit Bateau↑ longerLacoste Kids↑ longerCarter's↓ shorterLittle Planet by Carter's↓ shorterMini Mioche↑ longerOshKosh B'gosh↓ shorter+5 more | |
| 1662–64" | Petit Bateau↑ longerAppaman↑ longerLacoste Kids↑ longerJustice↓ shorterReebok Kids↓ shorterWalmart Wonder Nation↓ shorter+3 more | |
| 1862–64" | Petit Bateau↑ longerEddie Bauer↑ longerLee Jeans↑ longerMayoral↑ longerCalvin Klein Kids↑ longerBrooks Brothers Kids↑ longer+9 more |
Sizes shown use Old Navy’s girls’/unisex chart where the brand splits by gender; boys’ sizes at the same number can run slightly taller.
In short
Where the number just works. At 3-6M, 6-9M, 6T, Old Navy lines up with every brand we track — the size carries straight over.
Where labels drift. The exceptions are the “strangers” above — e.g. at size 5, Il Gufo cut the same number differently. Check those before you trust the label.
Bottom line: for most sizes, a Old Navy number is a safe bet elsewhere — measure once, then double-check only the handful of “stranger” brands above.
Curious about a size that isn’t your child’s here? Every size, compared across every brand, lives here: Browse all size comparisons →
Fit & the transitions that trip parents up
Old Navy-specific things the size number alone won’t tell you — drawn from its own charts.
Runs small — size up
Sizing up is the common advice, especially for babies, and some parents note snug necklines. Fit varies by item, but “size up” is the safe default.
Smaller than Gap, its sister brand
Within the Gap family (alongside Gap Kids and babyGap), Old Navy runs notably smaller than Gap itself — a size that fit in Gap often needs to go up a step here.
Plus to 20, plus a Slim cut
Old Navy publishes Plus for both girls and boys up to size 20 — one of the more inclusive body ranges we track — and a Slim cut for boys (5–12). It also publishes chest, waist and hips, so you can confirm the cut beyond height.
Specialty & inclusive fits
Which trimmer, roomier, or adaptive cuts Old Navy publishes alongside its standard sizes.
What shoppers say about the fit
Community consensus
Shopper opinion · not Little & Youth’s measurementThis is what parents report anecdotally — crowd sentiment, not a Little & Youth determination. Our sizing above is computed from Old Navy’s own published chart; the notes here come from public parent discussion.
Old Navy runs small — sizing up is the common advice, especially for babies, and some parents note snug necklines. Within the Gap family it runs notably smaller than Gap itself, so a size that fit in Gap often needs to go up a step here. Fit can vary by item, but “size up” is the safe default.
Based on anecdotal discussion from multiple publicly available online sources; your experience may differ.
Should you buy Old Navy?
Consider it if…
- You want the lowest price of the mainstream brands — value-tier with frequent deep sales.
- You want trend-forward everyday clothes — it leans more current than the plain-basics brands.
- You need extended sizes — it publishes Plus in kids up to 20 Plus, one of the more inclusive body ranges we track.
- You like data to size by — it publishes chest, waist and hips, so you can confirm the cut beyond height.
Think twice if…
- You shop on Amazon — Old Navy isn’t sold there; you’ll buy on oldnavy.com or in stores.
- You want premium fabric or durability — it’s value-tier: great for the price, not an heirloom line.
- You want timeless basics — it’s trend-driven, so styles turn over quickly.
Skip the cross-referencing — let Little & Youth do it.
Enter your child’s measurements once. We’ll show their Old Navy size and their size at 100+ other brands, each from that brand’s own chart.
Find my child’s size →Shop Old Navy ↗A few things parents ask that the chart won’t tell you
How much should I size up in Old Navy?
Usually one size, and most reliably for babies — that’s where the runs-small reputation is strongest and where parents mention snug necklines. Moving within the Gap family, plan to go up a step from Gap to Old Navy. Old Navy publishes chest, waist and hips but no weight, so confirm the jump with those body measurements rather than the age label.
Does Old Navy carry Plus or extended kids’ sizes?
Yes — it publishes Plus sizes in kids up to 20 Plus, which makes it one of the more size-inclusive mainstream brands. The specialty section above flags exactly what it offers.
Where can I buy Old Navy?
On oldnavy.com and in Old Navy stores.
Old Navy vs. Gap — which should I buy?
Same parent company, opposite ends. Old Navy is cheaper and more trend-driven but runs small; babyGap costs a bit more, runs roomier, and is a touch nicer. Expect to size up moving from Gap to Old Navy.
What measurements do I need to size Old Navy?
It publishes height, chest, waist, and hips (no weight). Height drives the size; the chest and waist figures help confirm the cut, which matters given the runs-small reputation.
Do Old Navy boys’ and girls’ sizes fit the same?
From the bigger sizes up, Old Navy publishes separate girls’ and boys’ charts, so the same number can differ by gender. The figures on this page use Old Navy’s girls’/unisex chart.
How do I choose between Old Navy’s regular, Slim and Plus cuts?
Each of these is the same numbered size as the regular cut — same length, adjusted through the waist and seat (Slim trimmer, Plus roomier). So size to your child’s usual Old Navy number from the chart above, then pick the cut by build: a smaller waist for Slim, a fuller waist and seat for the roomier cuts. You don’t need a separate measurement to choose.
How do Old Navy’s shoe and sock sizes work?
Old Navy carries kids’ shoes alongside its clothing. Kids’ shoe sizes go by foot length rather than age, and the same size number isn’t cut the same from brand to brand — so measure your child’s foot and check it against the chart. Old Navy’s socks are sized by shoe size, not age — buy for your child’s current shoe size, and if they fall between two ranges choose the smaller so the sock stays up. See how every kids’ shoe brand runs and how wide each is cut on our kids’ shoe sizing guide.