US to EU Ring Size Conversion
| US | EU |
|---|---|
| 4 | 47 |
| 4.5 | 48 |
| 5 | 49 |
| 5.5 | 50 |
| 6 | 51 |
| 6.5 | 52 |
| 7 | 54 |
| 7.5 | 55 |
| 8 | 57 |
| 8.5 | 58 |
| 9 | 59 |
| 9.5 | 60 |
| 10 | 61 |
Sizing conventions vary by brand and by cut — this table shows the standard published conversion. Always check the garment's own size chart when one is available. See how these tables are compiled.
From an arbitrary number to a direct circumference measurement
Of the three major ring-sizing conventions on this site, EU sizing is the most literal: the number you see (52, 54, 56...) is genuinely the internal circumference in millimetres, not a coded label the way a US or UK size is. Converting into EU is really converting into the real-world measurement itself.
Because the EU figure is a direct physical measurement, converting US to EU is arguably the most mechanically transparent of the three ring conversions — a US size 7 corresponds to roughly a 54mm EU/circumference size, and if you already know your circumference in millimetres from a jeweler's mandrel, you can skip the US-size step entirely and order EU sizing directly.
Where this specific direction is used
US shoppers hit this conversion most often ordering a custom or vintage-style ring from a French, Italian, or German maker sold direct-to-consumer online, where EU sizing is often the only option listed — because it's a direct measurement rather than a coded scale, mismatches here more often come from an out-of-date US reference size than from any imprecision in the conversion itself.
Skip the US step entirely if you can
A jeweler's mandrel reading in millimetres is the more direct input here — order EU sizing straight from that figure rather than routing it through a US number first, since each conversion step is one more place for a half-size to round the wrong way.
Why keeping the millimetre figure matters beyond this one purchase
Once you have an accurate circumference in millimetres, that number is useful for any future purchase from any of the three systems this site covers, not just a EU one — it’s worth writing down and keeping rather than re-deriving from a US size each time you shop a different region.
For a wedding or engagement purchase specifically, many jewelers offer free resizing within a window after purchase, which is worth confirming before you order if there’s any doubt about the converted figure.
Left and right hands commonly measure slightly differently on the same person, so if you’re converting a size for a ring meant for a specific hand, measure that exact hand rather than assuming the other one is close enough.
None of these secondary factors change the core conversion, which stays dependable across brands — they're simply the details that separate a size that's technically correct from one that actually feels right on the day you wear it.
Frequently asked questions
Is EU ring sizing more precise than US ring sizing?
In a sense yes — the EU number is literally the ring internal circumference in millimetres, while the US number is an arbitrary coded scale, so if you know your circumference directly, ordering by EU size skips a conversion step entirely.
Is a US size 7 always a 54mm EU ring size?
Check inside the band before you assume so — many European-made rings already have the millimetre circumference stamped on the inside, and that stamped number is worth trusting over a US-to-EU lookup table if the two ever disagree.
Why would a French or Italian jewelry site only list EU sizes?
Direct-to-consumer European makers size to their own domestic market by default; EU sizing being a literal circumference figure also means they have less reason to maintain a separate coded US-size chart.
How can I measure my circumference directly instead of converting a US size?
A jeweler's ring mandrel gives the most reliable reading, and a printable at-home sizer is a workable substitute — this site's dedicated ring-measuring guide walks through both methods step by step.