ASICS Size Guide
ASICS, founded in 1945 in Kobe, Japan by Kihachiro Onitsuka, is built on the philosophy that sport improves mental and physical health. The name derives from the Latin phrase "Anima Sana In Corpore Sano" — a sound mind in a sound body. Today, ASICS is renowned for cutting-edge sportswear, lifestyle trainers, and running shoes that prioritise comfort and performance. ASICS runs true to size in most styles; however, the brand recommends sizing up half a size when choosing running silhouettes to ensure optimal comfort during extended wear. The brand offers comprehensive size ranges across men's, women's, and children's collections, with extensive half-size availability.
How to Measure
- Chest: Measure around the fullest part of your chest, keeping the tape parallel to the ground. Do not pull tight.
- Waist: Measure around your natural waist (the narrowest point between your ribs and hips), with the tape sitting comfortably without constriction.
- Hips: Measure around the fullest part of your hips and seat, keeping the tape level and relaxed.
- Foot length: Stand on a flat surface with socks on. Measure from the back of your heel to the tip of your longest toe in centimetres.
- Tips for accuracy: Have someone else help you take measurements for the most precise results. If your measurements fall between two sizes, ASICS recommends ordering the larger size.
Men's Outerwear & Jackets
| Size | XS | S | M | L | XL | XXL | 3XL |
|---|---|---|---|---|---|---|---|
| Chest (cm) | 80–88 | 88–96 | 96–104 | 104–113 | 113–124 | 124–136 | 136–148 |
| Waist (cm) | 67–75 | 75–83 | 83–91 | 91–100 | 100–111 | 111–123 | 123–135 |
| Hips (cm) | 79–87 | 87–95 | 95–103 | 103–111 | 111–119 | 119–128 | 128–138 |
Women's Outerwear & Jackets
| Size | XXS | XS | S | M | L | XL | XXL |
|---|---|---|---|---|---|---|---|
| US | 4 | 6 | 8 | 10 | 12 | 14 | 16 |
| Chest (cm) | 69–75 | 75–82 | 82–89 | 89–96 | 96–104 | 104–114 | 114–124 |
| Waist (cm) | 52–58 | 58–65 | 65–72 | 72–79 | 79–87 | 87–96 | 96–107 |
| Hips (cm) | 76–82 | 82–89 | 89–96 | 96–103 | 103–111 | 111–119 | 119–127 |
Men's Trousers
| Size | XS | S | M | L | XL | XXL | 3XL |
|---|---|---|---|---|---|---|---|
| Waist (cm) | 67–75 | 75–83 | 83–91 | 91–100 | 100–111 | 111–123 | 123–135 |
| Hips (cm) | 79–87 | 87–95 | 95–103 | 103–111 | 111–119 | 119–128 | 128–138 |
Women's Trousers
| Size | XXS | XS | S | M | L | XL | XXL |
|---|---|---|---|---|---|---|---|
| US | 4 | 6 | 8 | 10 | 12 | 14 | 16 |
| Waist (cm) | 52–58 | 58–65 | 65–72 | 72–79 | 79–87 | 87–96 | 96–107 |
| Hips (cm) | 76–82 | 82–89 | 89–96 | 96–103 | 103–111 | 111–119 | 119–127 |
Men's Running & Lifestyle Shoes
| UK | US | EU | Foot Length (cm) |
|---|---|---|---|
| 5 | 6 | 39 | 24.5 |
| 5.5 | 6.5 | 39.5 | 25 |
| 6 | 7 | 40 | 25.25 |
| 6.5 | 7.5 | 40.5 | 25.5 |
| 7 | 8 | 41.5 | 26 |
| 7.5 | 8.5 | 42 | 26.5 |
| 8 | 9 | 42.5 | 27 |
| 8.5 | 9.5 | 43.5 | 27.5 |
| 9 | 10 | 44 | 28 |
| 9.5 | 10.5 | 44.5 | 28.25 |
| 10 | 11 | 45 | 28.5 |
| 10.5 | 11.5 | 46 | 29 |
| 11 | 12 | 46.5 | 29.5 |
| 11.5 | 12.5 | 47 | 30 |
| 12 | 13 | 48 | 30.5 |
| 13 | 14 | 49 | 31 |
| 14 | 15 | 50.5 | 32 |
| 15 | 16 | 51.5 | 33 |
Women's Running & Lifestyle Shoes
| UK | US | EU | Foot Length (cm) |
|---|---|---|---|
| 3 | 5 | 35.5 | 22.5 |
| 3.5 | 5.5 | 36 | 22.75 |
| 4 | 6 | 37 | 23 |
| 4.5 | 6.5 | 37.5 | 23.5 |
| 5 | 7 | 38 | 24 |
| 5.5 | 7.5 | 39 | 24.5 |
| 6 | 8 | 39.5 | 25 |
| 6.5 | 8.5 | 40 | 25.5 |
| 7 | 9 | 40.5 | 25.75 |
| 7.5 | 9.5 | 41.5 | 26 |
| 8 | 10 | 42 | 26.5 |
| 8.5 | 10.5 | 42.5 | 27 |
| 9 | 11 | 43.5 | 27.5 |
| 9.5 | 11.5 | 44 | 28 |
| 10 | 12 | 44.5 | 28.5 |
| 10.5 | 12.5 | 45 | 28.75 |
| 11 | 13 | 46 | 29 |
| 11.5 | 13.5 | 46.5 | 29.5 |
| 12 | 14 | 47 | 30 |
Children's Shoes
| UK | US | EU | Foot Length (cm) |
|---|---|---|---|
| K3 | K4 | 19.5 | 11.5 |
| K4 | K5 | 21 | 13 |
| K5 | K6 | 22.5 | 14 |
| K6 | K7 | 23.5 | 15 |
| K7 | K8 | 25 | 15.5 |
| K8 | K9 | 26 | 16 |
| K9 | K10 | 27 | 17 |
| K10 | K11 | 28.5 | 17.5 |
| K11 | K12 | 30 | 18.5 |
| K12 | K13 | 31.5 | 19.5 |
| K13 | 1 | 32.5 | 20 |
| 1 | 2 | 33.5 | 21 |
| 1.5 | 2.5 | 34.5 | 21.5 |
| 2 | 3 | 35 | 22 |
| 3 | 4 | 36 | 22.5 |
Product-Specific Guidance
Running Shoes
ASICS recommends sizing up half a size when selecting running trainers to allow adequate space for foot expansion during long-distance running and ensure comfort throughout your workout. This is particularly important for performance road running shoes and trail running silhouettes. Always measure your foot length in the afternoon when feet are slightly swollen, as this is when they are at their largest. The GEL-KAYANO, GEL-NYC, and GT-2160 are popular silhouettes that benefit from the half-size increase for extended wear.
Lifestyle & SportStyle Trainers
ASICS lifestyle trainers, including collaborations and the SportStyle range, run true to size and do not require sizing up. These contemporary streetwear-inspired models maintain the brand's core comfort standards whilst offering modern aesthetics. Order your usual size for optimal fit.
Socks
| Size | S | M | L | XL | XXL |
|---|---|---|---|---|---|
| EU Shoe Size | 35–38 | 39–42 | 43–46 | 47–49 | 50–52 |
| UK Shoe Size | 2.5–5 | 5.5–8 | 8.5–11 | 11.5–13 | 13–14.5 |
Backpacks
| Size | S | M | L |
|---|---|---|---|
| Chest (cm) | 93–99 | 99–105 | 105–111 |
Sizing Tips
- Running shoes half-size rule: Always size up half a size in running trainers to accommodate foot swelling during extended athletic activity and ensure proper toe clearance within the toebox.
- Measure in the afternoon: Your feet are naturally larger in the afternoon and evening due to swelling from daily activity. Measure at this time for the most accurate sizing, particularly for shoes you plan to wear during training.
- Half-size availability: ASICS offers comprehensive half-size options across men's and women's trainers, making it easy to find your precise fit without settling for a full size up or down.
- Between-size guidance: If your measurements fall between two sizes, ASICS recommends selecting the larger size for comfort, particularly in clothing where a relaxed fit is preferable to a tight garment.
- Get professional fitting: Visit an ASICS store or authorised retailer for in-store fitting assistance, especially when purchasing running shoes. Staff can provide gait analysis and personalised recommendations.
- Consider sock thickness: Measure your foot whilst wearing the socks you intend to wear with your trainers, as thick cushioned running socks can affect the final fit.
- Allow for growth in children's styles: When fitting children's ASICS trainers, leave approximately 1–1.5 cm clearance at the toe to allow room for natural foot growth during the season.
- Check return policies: ASICS offers free UK returns into stores for most items, so if your first size doesn't feel quite right, you can exchange with confidence.