Gap Size Guide
Gap is an iconic American casualwear brand that has been a wardrobe staple since 1969, renowned for its classic denim, soft cotton essentials, structured shirts, and timeless outerwear. With a sizing philosophy rooted in relaxed, comfortable fits, Gap caters to men, women, and children who appreciate well-made basics with an effortless style. As Gap uses US sizing on its labels — even when sold in the UK — understanding how their sizes convert is essential for getting the right fit first time. Gap is known for slightly generous sizing, particularly in casual tops and denim, so always refer to actual body measurements rather than relying solely on your usual UK size. The brand also offers Petite sizing (designed for those under 5’4″ / 162cm) and Tall sizing (for those over 5’8″ / 172cm) in select women’s styles, available exclusively online.
How to Measure
- Bust / Chest: Measure around the fullest part of your chest, keeping the tape measure level and snug but not tight. Wear a well-fitting, non-padded bra if measuring for women’s clothing.
- Waist: Measure around your natural waistline. To find this, bend to one side — the crease that forms is your natural waist. Keep the tape comfortably snug.
- Hips: Stand with your feet together and measure around the fullest part of your hips and buttocks.
- Inside Leg: Run a tape measure from the top of your inner thigh down to your ankle bone. It helps to measure a pair of well-fitting trousers laid flat if you find this difficult.
- Neck (Men): Measure around the base of your neck, where your collar would sit, adding approximately half an inch for comfort.
- Sleeve: With your arm bent at 90 degrees and your hand on your hip, measure from the centre back of your neck, across your shoulder, down past your elbow to your wrist.
- Height: Stand barefoot on a flat surface with your feet together, looking straight ahead. Ask someone to measure from the top of your head to the floor.
Women’s Clothing Size Chart
| Size Label | UK | US | EU | Bust (inches) | Waist (inches) | Hip (inches) |
|---|---|---|---|---|---|---|
| 2XS / XXS | 2 | 00 | 30 | 31 | 24.5 | 34 |
| XS | 4–6 | 0–2 | 32–34 | 32–33 | 25.5–26.5 | 35–36 |
| S | 8–10 | 4–6 | 36–38 | 34–35 | 27.5–28.5 | 37–38 |
| M | 12–14 | 8–10 | 40–42 | 36–37 | 29.5–30.5 | 39–40 |
| L | 16–18 | 12–14 | 44–46 | 38–40 | 32–33.5 | 41.5–43 |
| XL | 20–22 | 16–18 | 48–50 | 42–43 | 35.5–37.5 | 45–47 |
| 2XL / XXL | 24 | 20 | 52 | 45–47 | 39.5–41.5 | 49–51 |
Women’s Jeans Size Chart
Gap women’s jeans are listed by waist size in inches. Use this chart to find the corresponding UK, US, and EU sizes along with body measurements.
| Jean Size (Waist in) | UK | US | EU | Alpha Size | Waist (inches) | Hip (inches) |
|---|---|---|---|---|---|---|
| 24 | 4 | 00 | 32 | XXS | 24.5 | 34.25 |
| 25 | 6 | 0 | 34 | XS | 25.5 | 35.25 |
| 26 | 8 | 2 | 36 | S | 26.5 | 36.25 |
| 27 | 8–10 | 4 | 36–38 | S | 27.5 | 37.25 |
| 28 | 10 | 6 | 38 | S | 28.5 | 38.25 |
| 29 | 12 | 8 | 40 | M | 29.5 | 39.25 |
| 30 | 12–14 | 10 | 40–42 | M | 30.5 | 40.25 |
| 31 | 14 | 12 | 42 | M | 32 | 41.75 |
| 32 | 16 | 14 | 44 | L | 33.5 | 43.25 |
| 33 | 18 | 16 | 46 | XL | 35.5 | 45.25 |
| 34 | 20 | 18 | 48 | XXL | 37.5 | 47.25 |
Women’s Jeans & Trousers — Inside Leg Lengths
| Length | Full Length Inseam (inches) | Full Length Inseam (cm) | Ankle Length Inseam (inches) | Ankle Length Inseam (cm) |
|---|---|---|---|---|
| Petite (P) / X-Short | 27.5 | 70 | 25 | 63.5 |
| Short (S) | 29 | 74 | 26 | 66 |
| Regular (R) | 30 | 76 | 27.5 | 70 |
| Long (L) | 31 | 83 | 29.5 | 75 |
| Tall / X-Long | 34 | 86 | 32 | 81 |
Women’s Dresses Size Chart
| Size Label | UK | US | EU | Bust (inches) | Waist (inches) | Hip (inches) |
|---|---|---|---|---|---|---|
| XXS | 2–4 | 00–0 | 30–32 | 31–32.25 | 24–25.5 | 34.25–35.25 |
| XS | 6 | 2 | 34 | 33.25 | 26.5 | 36.25 |
| S | 8–10 | 4–6 | 36–38 | 34.25–35.25 | 27.5–28.5 | 37.25–38.25 |
| M | 12–14 | 8–10 | 40–42 | 36.25–37.25 | 29.5–30.5 | 39.25–40.25 |
| L | 16–18 | 12–14 | 44–46 | 38.75–40.25 | 32–33.5 | 41.75–43.25 |
| XL | 20–22 | 16–18 | 48–50 | 42–43.75 | 35.5–37.5 | 45.25–47.25 |
| XXL | 24–26 | 20–22 | 52–54 | 45.75–47.75 | 39.5–41.5 | 49.25–51.25 |
Men’s Tops, Shirts & Outerwear Size Chart
| Size Label | UK | US | EU | Neck (inches) | Chest (inches) | Sleeve (inches) |
|---|---|---|---|---|---|---|
| XS | 36 | XS | 46 | 14 | 36 | 32 |
| S | 38 | S | 48 | 14.5 | 38 | 33 |
| M | 40 | M | 50 | 15.5 | 41 | 34 |
| L | 43 | L | 53 | 16.5 | 44 | 35 |
| XL | 47 | XL | 57 | 17.5 | 48 | 35.5 |
| XXL | 51 | XXL | 61 | 18.5 | 52 | 36 |
Men’s Jeans Size Chart
Gap men’s jeans are sold by waist size in inches. Below is the full range with alpha and EU conversions.
| Jean Size (Waist in) | Alpha Size | EU | Waist (inches) | Waist (cm) |
|---|---|---|---|---|
| 28 | XS | 38 | 28 | 71 |
| 29 | XS | 39 | 29 | 73.5 |
| 30 | S | 40 | 30 | 76 |
| 31 | S | 41 | 31 | 79 |
| 32 | M | 42 | 32 | 81.5 |
| 33 | M | 43 | 33 | 84 |
| 34 | M | 44 | 34 | 86.5 |
| 36 | L | 46 | 36 | 91.5 |
| 38 | XL | 48 | 38 | 96.5 |
| 40 | XL | 50 | 40 | 101.5 |
| 42 | XXL | 52 | 42 | 107 |
Men’s Jeans & Trousers — Inside Leg Lengths
| Length | Inseam (inches) | Inseam (cm) |
|---|---|---|
| Short | 30 | 76 |
| Regular | 32 | 81.5 |
| Long | 34 | 86.5 |
Men’s XS–XXL Jeans (Alpha Sizing)
Some Gap men’s jeans and jogger-style trousers use alpha sizing rather than waist inches. Use this chart if your garment is labelled XS–XXL.
| Alpha Size | Waist Range (inches) | Waist Range (cm) |
|---|---|---|
| XS | 28–29 | 71–74 |
| S | 30–31 | 76–79 |
| M | 32–34 | 81–86 |
| L | 35–37 | 89–94 |
| XL | 38–41 | 97–104 |
| XXL | 42–45 | 107–114 |
Product-Specific Guidance
Gap Jeans — Women’s
Gap has been making jeans since 1969 and their women’s denim is one of the brand’s most popular categories. Women’s jeans are listed by waist size in inches (24–34), not by UK dress size, so always check the conversion chart above. Be aware that Gap denim can run slightly large in the waist but narrower through the hips, and many styles contain stretch fabric that will give after a few wears. If you are between sizes, consider sizing down. Popular fits include the High Rise Cheeky Straight, ’90s Loose, and Classic Straight. Always check the inside leg length — Gap offers five lengths from Petite (27.5″) through to Tall (34″), so you can find the perfect crop or full-length fit for your height.
Gap Jeans — Men’s
Men’s jeans use straightforward waist-inch sizing from 28 to 42. The waist measurement on the label corresponds directly to your actual waist measurement in inches, making selection relatively simple. Choose between Short (30″), Regular (32″), and Long (34″) inside leg options. Gap offers multiple fits including Slim, Straight, Athletic, and Relaxed — the same waist size can feel quite different across these styles, so read the product description carefully.
Gap T-Shirts, Hoodies & Casual Tops
Gap’s cotton basics — including the iconic logo hoodie and Vintage Soft range — tend to run generously. If you prefer a more fitted look, consider sizing down. Oversized and relaxed-fit styles are designed to be roomy, so choose your usual size if you want that intended silhouette. Gap has been making hoodies and sweatshirts for over 30 years, and cropped, fitted, and oversized designs are all available.
Gap Outerwear
Jackets and coats from Gap typically have a relaxed cut, particularly through the shoulders and armholes. Use your chest measurement as the primary guide. If you plan to layer knitwear underneath, your regular size should accommodate this; if wearing over a thin top only, you may wish to size down for a neater silhouette.
Gap Shirts (Men’s)
Men’s dress and casual shirts use alpha sizing (XS–XXL). The neck measurement is key for formal shirts — sizes range from 14″ (XS) to 18.5″ (XXL). Always cross-reference your neck and chest measurements against the chart above, as a comfortable collar fit is essential.
Shoe Size Conversion Chart
Gap sells select footwear including trainers, sandals, and boots for women, men, and children. As footwear uses US sizing on the label, this conversion chart will help you find the correct UK and EU equivalent.
| UK | US Men’s | US Women’s | EU | Foot Length (cm) |
|---|---|---|---|---|
| 3 | – | 5 | 36 | 22.5 |
| 3.5 | – | 5.5 | 36.5 | 22.8 |
| 4 | – | 6 | 37 | 23.5 |
| 4.5 | – | 6.5 | 37.5 | 23.8 |
| 5 | – | 7 | 38 | 24 |
| 5.5 | 6 | 7.5 | 38.5 | 24.3 |
| 6 | 7 | 8 | 39 | 24.5 |
| 6.5 | 7.5 | 8.5 | 40 | 25 |
| 7 | 8 | 9 | 41 | 25.5 |
| 7.5 | 8.5 | 9.5 | 41.5 | 25.7 |
| 8 | 9 | 10 | 42 | 26.5 |
| 8.5 | 9.5 | 10.5 | 42.5 | 26.8 |
| 9 | 10 | 11 | 43 | 27 |
| 9.5 | 10.5 | – | 43.5 | 27.5 |
| 10 | 11 | – | 44 | 28 |
| 10.5 | 11.5 | – | 44.5 | 28.5 |
| 11 | 12 | – | 45 | 29 |
| 12 | 13 | – | 46 | 29.5 |
Gap Size 4 — What Does It Mean in UK Sizing?
A Gap US size 4 is equivalent to a UK size 8 (EU 36). This falls within Gap’s “Small” alpha sizing. For jeans, this corresponds approximately to a waist 27 jean size. If you usually wear a UK 8, look for US 4 or S in Gap clothing. Note that because Gap uses US labelling, the number on the tag may be lower than you expect — a UK 10 shopper should look for a US 6, a UK 12 for a US 8, and so on.
Understanding Gap XS & XL Sizing
XS in women’s: Covers UK 4–6 (US 0–2, EU 32–34), with a bust of approximately 32–33″ and waist of 25.5–26.5″. XL in women’s: Covers UK 20–22 (US 16–18, EU 48–50), with a bust of approximately 42–43″ and waist of 35.5–37.5″. For men, XS fits a 36″ chest and XL fits a 48″ chest.
Sizing Tips
- US labels on UK orders: Gap garments are often labelled with US sizing even when purchased in the UK. Don’t be alarmed if the tag shows a smaller number than your usual UK size — always refer to the conversion charts above.
- Denim stretches: Gap jeans, particularly those with elastane or Lycra blends, will stretch with wear. If you’re between two jean sizes, opt for the smaller size as the fabric will ease to fit your body within a few wears.
- Read the fit description: The same size can feel very different across Gap’s various fits. An “Oversized” or “Boyfriend” style is intentionally roomy, while “Slim” and “Fitted” styles are more tailored. Always check the product page for fit-specific guidance.
- Consider your inside leg length: Gap offers up to five leg length options for women (Petite, Short, Regular, Long, and Tall) and three for men (Short, Regular, Long). Choosing the correct length is just as important as the waist size for a polished look.
- Casual tops run generous: Gap’s T-shirts, hoodies, and sweatshirts are known for relaxed, slightly oversized fits. If you prefer a neater, more tailored appearance, size down by one. If you enjoy the relaxed feel, stick with your usual size.
- Measure, don’t guess: Because Gap’s sizing philosophy is on the generous side, your body measurements are more reliable than your habitual UK size. Take fresh measurements before ordering, especially if you haven’t shopped with Gap recently.
- Check product pages for specific charts: Sizes and exact fits may vary between clothing types and fabrics. Gap provides product-specific size guides on individual pages, which may differ slightly from the general charts — always double-check before adding to your basket.
- BabyGap & kids’ sizing uses US age guides: Children’s clothing follows US age and height standards, which may not align with UK expectations. A child who typically wears a UK age 12–18 months may need a smaller BabyGap size — always check the height range in centimetres for the most accurate fit.