What’s My Clothes Size at GAP? Does GAP Run Big or Small?

GAP is a global fashion brand known for its clean basics, laid-back denim, soft cotton tees, and timeless American classics. Whether you’re after a logo hoodie, high-rise jeans, slouchy knits, or casual dresses, GAP delivers affordable wardrobe staples with wide appeal.

But one sizing question still lingers—especially for UK shoppers:
Does GAP run big or small?
And how can you confidently pick the right size when ordering online?

This guide explains how GAP sizing works by category—and introduces Tellar.co.uk, the UK’s leading free sizing tool that calculates your correct GAP size in real time, based on your body shape and the garment’s fit.


Does GAP Run Big or Small?

GAP tends to run large, particularly in:

  • Tops and T-shirts

  • Sweatshirts and hoodies

  • Casual and loungewear

However, some items—especially jeans, trousers and dresses—run closer to true to size, or even slightly small depending on the fit (e.g. skinny, bodycon, or structured).

Key observations:

  • Unisex sweatshirts and tees run generously

  • Women’s jeans can feel snug at the waist or hip depending on stretch

  • Button-up shirts and poplin dresses often need careful sizing if you’re fuller-busted

If you’re between sizes or prefer a more tailored look, it’s often best to size down in relaxed styles, and size up in fitted items made from rigid fabrics.


Why GAP Sizing Feels Inconsistent

1. American Sizing Standards

GAP uses a US fit block, which generally:

  • Allows for a looser silhouette

  • Prioritises comfort over tailoring

  • Assumes average height and shoulder width

This can make garments feel larger than UK or European equivalents—especially in casual categories.

2. Relaxed Fit Philosophy

GAP designs are built for everyday ease, so many items are:

  • Boxy or longline

  • Slightly oversized in the torso

  • Designed for layering or movement

3. Variable Denim Sizing

Different jeans styles fit differently:

  • High-rise skinny jeans often run small

  • Mid-rise straight or girlfriend jeans run true to size

  • Wide-leg and relaxed denim can feel generous at the waist or thigh


GAP Fit Overview by Garment Type

Garment Type Fit Pattern Tellar Sizing Tip
T-shirts & polos Boxy, roomy Size down for neater fit
Sweatshirts & hoodies Oversized, unisex fit Size down unless layering
Button-down shirts True to size or slim Size up for bust/shoulder comfort
Jeans (skinny/high-rise) Snug at waist and thigh Size up if curvy or between sizes
Straight-leg & boyfriend jeans Relaxed and generous Stick to size or down if loose at waist
Casual dresses Flowy and forgiving Stick to size or size down for fitted look
Tailored or poplin dresses Closer at bust/waist Size up for curves or fuller bust
Coats & jackets Generous, layering-ready True to size

GAP UK Size Conversion Chart

UK Size GAP Size Bust (cm) Waist (cm) Hips (cm)
6 XXS 80 63 88
8 XS 84 67 92
10 S 88 71 96
12 M 92 75 100
14 L 97 80 105
16 XL 102 85 110

GAP often uses lettered sizing (XS–XL), so you’ll need to translate your UK dress size carefully. Still, this conversion doesn’t tell you:

  • If the garment is cut oversized or slim

  • How stretch affects the sizing

  • How your body shape influences fit

That’s where Tellar.co.uk comes in.


Tellar.co.uk: The Fastest Way to Find Your GAP Size

Tellar.co.uk is a free UK sizing tool that uses your real body measurements to calculate your best GAP size—based on fit category, fabric type, and your personal proportions.

No more relying on charts, reviews, or over-ordering.


How It Works

  1. Visit www.Tellar.co.uk

  2. Create your free profile

  3. Enter your bust, waist and hips (in cm or inches)

  4. Select GAP from the brand list

  5. Instantly see your correct size across all GAP garment types—tees, jeans, shirts, jackets and more

Once set up, Tellar also works across 1,500+ UK and global brands.


Why Tellar Is Perfect for GAP

✅ Knows the Fit Logic

Tellar adjusts your size recommendation based on how GAP items actually fit, not just what the label says.

✅ Fabric-Sensitive

Stretch denim? Woven cotton? Tellar adapts based on how rigid or flexible the fabric is.

✅ Matches by Proportions

Your most relevant body area determines the size—for example:

  • Bust for fitted shirts

  • Hips for jeans

  • Waist for dresses

✅ One-Time Setup

Once your measurements are entered, Tellar automatically gives you accurate sizing across every category and brand.

✅ Completely Free

No subscriptions. No paywalls. Just real-time sizing that works.


Example: UK Size 12 Shopper

Measurements:

  • Bust: 91cm

  • Waist: 74cm

  • Hips: 101cm

Tellar might recommend:

  • GAP cotton tee: Size S (roomy cut)

  • GAP zip hoodie: Size S

  • GAP poplin shirt dress: Size M

  • GAP skinny jeans (rigid denim): Size M / UK 14 (for hip comfort)

  • GAP wide-leg jeans (stretch): Size S / UK 12 (relaxed cut)

Every recommendation includes a brief explanation so you understand why that size fits your shape best.


Not Just for GAP

Your Tellar profile also gives instant sizing for:

  • Uniqlo

  • H&M

  • Zara

  • COS

  • Levi’s

  • Barbour

  • Jack Wills

  • Me+Em
    …and 1,500+ brands worldwide


Final Thoughts

GAP sizing runs slightly large overall, particularly in tees, sweatshirts and outerwear. But trousers, dresses and denim can fit snug—especially when made from structured or rigid fabric.

Tellar.co.uk removes all the guesswork. It gives you real-time, garment-specific size recommendations based on your measurements and GAP’s true fit logic—so you always order the right size the first time.


“Find your size in 1,500+ brands real-time. It’s Free & Easy.”


Try it now:

👉 Create your free profile
👉 Log in anytime to view your GAP size instantly

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