4F Size Guide
4F is a sportswear and lifestyle brand offering activewear, trainers, outerwear, and casual clothing for men and women. Like many European apparel labels, 4F primarily uses EU sizing, with UK and US equivalents provided for international shoppers. The brand’s fit philosophy centres on comfort and performance: garments are cut for movement, and technical pieces are often designed with a little extra room through the chest and shoulders so you can layer underneath. Everyday sportswear tends to run true to size, whilst insulated jackets, ski wear, and winter boots may feel slightly more generous to accommodate thermal layers and thicker socks. Use the charts below as a starting point, then cross-check your body or foot measurements before ordering.
How to Measure
- Chest (men) / Bust (women): Measure around the fullest part of your chest or bust, keeping the tape level and parallel to the floor. The tape should sit comfortably under your arms without digging in.
- Waist: Measure around your natural waistline — the narrowest point above your navel where your body creases when you bend slightly forward.
- Hips: Stand with feet together and measure around the fullest part of your hips and bottom, keeping the tape horizontal.
- Inside leg: Measure from the top of your inner thigh at the crotch down to the floor whilst wearing the shoes you normally pair with trousers.
- Foot length: Stand on a sheet of paper with your heel against a wall, mark the tip of your longest toe, and measure the distance in centimetres. Measure both feet and use the longer measurement; shop for the larger foot.
- Timing: Take body measurements over light clothing and measure feet in the afternoon or evening, when slight swelling gives a more reliable all-day fit.
Women’s Clothing Size Chart
4F women’s clothing follows standard EU sizing. Match your measurements to the row that fits your largest dimension; if you fall between sizes, size up for outerwear and fitted sportswear.
| Size Label | UK | US | EU | Chest (inches) | Waist (inches) | Hips (inches) |
|---|---|---|---|---|---|---|
| XS | 6 | 2 | 34 | 31–33 | 24–25 | 33–35 |
| S | 8 | 4 | 36 | 33–35 | 26–27 | 35–37 |
| M | 10 | 6 | 38 | 35–37 | 27–28 | 37–39 |
| L | 12 | 8 | 40 | 37–39 | 29–30 | 39–41 |
| XL | 14 | 10 | 42 | 39–41 | 31–32 | 41–43 |
| XXL | 16 | 12 | 44 | 41–43 | 33–34 | 43–45 |
| XXXL | 18 | 14 | 46 | 43–45 | 35–36 | 45–47 |
Men’s Clothing Size Chart
4F men’s tops and jackets are sized by chest measurement. Trousers follow waist sizing aligned to the same alpha label. Athletic cuts suit most builds true to size; choose one size up if you plan heavy mid-layering under a ski or hiking jacket.
| Size Label | UK | US | EU | Chest (inches) | Waist (inches) | Hips (inches) |
|---|---|---|---|---|---|---|
| XS | 32 | XS | 44 | 34–36 | 28–29 | 34–36 |
| S | 34 | S | 46 | 36–38 | 29–30 | 36–38 |
| M | 36 | M | 48 | 38–40 | 30–31 | 38–40 |
| L | 40 | L | 50 | 40–42 | 32–33 | 40–42 |
| XL | 42 | XL | 52 | 42–44 | 34–35 | 42–44 |
| XXL | 44 | XXL | 54 | 44–46 | 36–37 | 44–46 |
| XXXL | 46 | XXXL | 56 | 46–48 | 38–39 | 46–48 |
Women’s Footwear Size Chart
4F women’s trainers and casual shoes follow standard EU footwear sizing. Measure foot length in centimetres and match to the closest EU size; allow roughly one thumb’s width of toe room in athletic styles.
| UK | US Men’s | US Women’s | EU | Foot Length (cm) |
|---|---|---|---|---|
| 3 | 4 | 5 | 36 | 22.5 |
| 3.5 | 4.5 | 5.5 | 36.5 | 22.9 |
| 4 | 5 | 6 | 37 | 23.3 |
| 4.5 | 5.5 | 6.5 | 37.5 | 23.7 |
| 5 | 6 | 7 | 38 | 24.0 |
| 5.5 | 6.5 | 7.5 | 38.5 | 24.6 |
| 6 | 7 | 8 | 39 | 24.9 |
| 6.5 | 7.5 | 8.5 | 39.5 | 25.4 |
| 7 | 8 | 9 | 40 | 25.8 |
| 7.5 | 8.5 | 9.5 | 40.5 | 26.2 |
| 8 | 9 | 10 | 41 | 26.5 |
| 8.5 | 9.5 | 10.5 | 41.5 | 26.9 |
| 9 | 10 | 11 | 42 | 27.3 |
Men’s Footwear Size Chart
4F men’s trainers, running shoes, and outdoor boots use EU sizing. Women’s sizes run approximately 1.5 sizes smaller than men’s at the same EU number — a women’s EU 39 is not equivalent to a men’s EU 39. Between two sizes, sizing up half a size is usually more comfortable for sport and hiking footwear.
| UK | US Men’s | US Women’s | EU | Foot Length (cm) |
|---|---|---|---|---|
| 6 | 7 | 8 | 39 | 24.5 |
| 6.5 | 7.5 | 8.5 | 40 | 25.0 |
| 7 | 8 | 9 | 41 | 25.5 |
| 7.5 | 8.5 | 9.5 | 41.5 | 25.8 |
| 8 | 9 | 10 | 42 | 26.5 |
| 8.5 | 9.5 | 10.5 | 42.5 | 26.9 |
| 9 | 10 | 11 | 43 | 27.3 |
| 9.5 | 10.5 | 11.5 | 43.5 | 27.7 |
| 10 | 11 | 12 | 44 | 28.0 |
| 10.5 | 11.5 | 12.5 | 44.5 | 28.3 |
| 11 | 12 | 13 | 45 | 28.7 |
| 11.5 | 12.5 | 13.5 | 45.5 | 29.2 |
| 12 | 13 | 14 | 46 | 29.5 |
| 13 | 14 | — | 47 | 30.5 |
Product-Specific Guidance
Trainers & running shoes: 4F trainers are generally true to EU size when matched by foot length. Running styles benefit from a little extra toebox room; if your measurement sits between two EU sizes, choose the larger. Wider feet may feel more comfortable in half a size up, particularly in narrow-lasted road-running models.
Ski jackets & outdoor outerwear: Insulated and waterproof jackets are cut to fit over a base layer and mid-layer. Your regular clothing size should work for most builds; size up if you prefer a looser fit or wear bulky fleece underneath. Sleeve lengths on technical outerwear are slightly longer than casual tops to cover the wrist when arms are raised.
Hoodies & sportswear tops: Casual hoodies, T-shirts, and training tops follow a modern athletic fit close to the body without restricting movement. True-to-size works for a neat look; size up for a relaxed off-pitch fit or if your chest measurement falls at the top of a size range.
Joggers & trousers: Waist sizing aligns with the alpha chart above. Check inside-leg guidance on the product page — leg lengths are typically offered as short (30″), regular (32″), or long (34″). Slim and tapered cuts suit your usual size; relaxed outdoor trousers may feel roomier through the thigh at the same waist label.
Thermal base layers: Base layers and thermals should fit snugly against the skin to wick moisture effectively. Choose your normal clothing size; only size up if you plan to wear two thermal layers stacked beneath a single outer shell.
Sizing Tips
- 4F labels primarily show EU sizes — always convert using the charts above rather than assuming your usual UK high-street number will match.
- Measure feet in the evening and fit to your longer foot; athletic shoes need roughly 10–15 mm of space beyond your longest toe.
- For winter jackets, ski trousers, and hiking boots, factor in layering: thermal tops and thick socks add volume that a summer-weight size guide does not account for.
- If your chest and waist measurements point to different sizes, prioritise the larger measurement for outerwear and the smaller for close-fitting base layers.
- Women’s and men’s footwear are not interchangeable at the same EU number; women’s sizes run about 1.5 sizes smaller than men’s.
- Between two sizes in trainers or boots, half a size up is usually more comfortable than sizing down.
- Check the product description for fit notes — some 4F collections are labelled slim, regular, or oversized and may shift the recommended size.
- Inside-leg length matters as much as waist size for joggers and outdoor trousers; a correct waist with the wrong leg length will still feel wrong.