Complete 2026 UK standard ring sizes A–Z+6 · Diameter & circumference in mm · US, EU, French & Japanese conversions · Calculator & expert tips.
Most common women's size in UK. Equivalent to US 6–6.5 and EU 51–52. Data from H.Samuel, Serendipity Diamonds and Allure Jewellers research.
Most common men's size in UK. Equivalent to US 9–9¾ and EU 60–61. Data from Hitched, Regal Hatton Garden and Queensmith industry surveys.
| 🇬🇧 UK | ⭕ Circ. MM | ⭕ Circ. CM | 📐 Diam. MM | 📐 Diam. CM | 🇺🇸 US | 🇩🇪 EU | 🇫🇷 French | 🇯🇵 Japan | Range |
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Wrap a paper strip around your ring finger. Mark the overlap. Measure in mm with a ruler. This is your circumference.
Look up your mm reading in the Circ. MM column. If between two sizes, choose the larger one.
Enter mm, cm or inches (diameter or circumference) for an instant UK size + US · EU · French · Japan conversion.
Measure the inner diameter of a well-fitting ring using calipers. Find it in the Diam. MM column to confirm.
Read across the row for your UK size to find the equivalent US, EU, French or Japanese size to order safely.
For engagement and wedding rings, always have your finger measured by a UK jeweller — it's free and takes 2 minutes.
Measure in the afternoon or evening. Fingers are largest then. Avoid cold mornings or post-exercise — your reading will be inaccurate.
Always measure the exact finger the ring will be worn on. Your dominant hand ring finger is usually half a size larger than the other hand.
If your measurement falls between two sizes, always choose the larger one. A slightly loose ring is easy to fix — a tight one isn't.
Bands wider than 6mm feel tighter than their nominal size. Go up half a UK size for 6–8mm bands, a full size for 10mm+.
Your ring must pass over the knuckle. If your knuckle is significantly wider than your finger base, size to fit the knuckle and use a ring adjuster.
Never assume size names match across countries. A US "Size 7" ≠ French "Size 7". Always convert using mm or this chart before ordering.