A jacket size chart converts chest measurement in inches to a size: 34–36″ is XS, 36–38″ is S, 38–41″ is M, 40–44″ is L, and 44–47″ is XL. Match your exact chest number to the range, not the label alone.
Your chest measurement decides most of your jacket size. Match it against a standard size chart, and you’ll land on the right fit almost every time.
This guide breaks down the full jacket size chart for men, women, and kids, plus a dedicated suit jacket size chart with US-to-UK-to-EU conversions — along with the exact steps to measure yourself at home.
Mens Jacket Size Chart
A mens jacket size chart runs on chest circumference. Brands like SYNC Performance, The Jacket Maker, and ASOS all build their charts around this one number, though the exact inch ranges shift slightly from label to label.
Kids’ sizing skips chest measurements almost entirely. It’s built on age, height, and weight instead, since children’s proportions change too fast for chest-based logic to hold up.
Age/Size
Height (in)
Weight (lbs)
2T
33–36
24–33
3T–4T
36–42
33–40
5–6
42–48
40–53
7–8
48–52
53–72
9/10
53–57
73–84
11/12
57–59
85–96
14
60–65
97–120
How To Measure Jacket Size
Skip the guesswork. Grab a soft measuring tape and a light shirt — never measure over a thick sweater or bare skin, both throw the number off.
Chest: Wrap the tape around the fullest part of your chest, under the arms, keeping it level.
Shoulder width: Measure across the back, tip of one shoulder to the other.
Sleeve length: From the shoulder seam to your wrist bone, arm slightly bent.
Body length: Top of the shoulder down to where you want the jacket to end.
Round your chest number up, never down. A snug jacket restricts movement; a slightly loose one still looks sharp.
Suit Jacket Size Chart
It’s built with structured shoulders, a defined waist suppression, and a drop — the gap between chest and waist measurements — that a casual jacket never accounts for.
Mens Suit Jacket Size Chart
The drop on a standard mens suit jacket sits around 6 inches (chest minus waist). Lengths break into Short, Regular, and Long, based on your height.
Size
Chest (in)
Waist (in)
Sleeve (in)
Length
36R
37
31
18
5’7″–5’9″
38R
39
33
18
5’7″–5’9″
40R
41
35
18
5’9″–6′
42R
43
37
18
5’9″–6′
44R
45
39
18
5’9″–6′
46L
47
41
19
6’–6’4″
Womens Suit Jacket Size Chart
Women’s suit jackets follow a tighter bust-to-waist drop, usually around 10 inches, giving the blazer its tailored, fitted silhouette.
Tailoring rewards precision. A suit jacket needs three extra checks beyond a casual piece.
Natural waist: Measure at the narrowest point, usually right at the navel — this feeds your drop calculation.
Chest, arms raised slightly: Lifting the arms just past parallel gives an accurate reading across the shoulder blades.
Jacket length by height: Short fits under 5’9″, Regular between 5’9″ and 6′, Long above 6′.
A tailor can adjust sleeve length and take in a waist by an inch or two. Chest width and shoulder seams are far harder — and pricier — to alter, so get those two right first.
FAQs
What is a 42 size jacket?
A size 42 jacket fits a chest measurement of about 42 to 44 inches, which lands in the Large range.
How do I know my size for a jacket?
Measure your chest circumference at its fullest point and match the number to a jacket size chart.
Is 42 size XL or L?
A 42 is a Large, not an XL, in standard US jacket sizing.
Is a size 40 jacket medium or large?
A size 40 jacket typically falls under Medium in US charts.
I am the admin and author of SizesForm, researching, verifying, and explaining measurements, dimensions, weights, and sizes in simple terms to help readers understand everyday comparisons accurately and confidently.
