US 4 in every sizing system
| US / Canada | UK / Australia | EU / ISO (circumference, mm) | Japan / Korea | Inside diameter (mm) |
|---|---|---|---|---|
| US 3.5 | G½ | 45.5 | 5 | 14.5 |
| US 4This size | H½ | 46.8 | 7 | 14.9 |
| US 4.5 | I½ | 48.0 | 8 | 15.3 |
What a size 4 ring measures
Inside diameter 14.9 mm (about 0.59 in), inside circumference 46.8 mm. Measuring a ring that already fits? Measure the inside edge to edge for the diameter. Measuring a finger? Wrap a strip of paper around its base and compare the overlap with the circumference.
Is US 4 a common ring size?
US 4 is below the 4.5 to 7.5 range most women's engagement rings are stocked in. Many designs can be made or resized down to it, but ask before ordering a setting with stones around the band.
Between two sizes?
Take the larger one. A ring is easier to make smaller than larger, a wide band needs a little more room than a thin one, and fingers swell in heat and in the evening. A jeweler's sizer set settles it in a minute.
Convert a measurement to a ring size
Measure a ring that already fits the right finger, or the finger itself, and enter the number in millimeters.
Quick answers
Frequently asked questions
What is a US ring size 4 in mm?
US 4 is 14.9 mm across the inside and 46.8 mm around the inside. The millimeter circumference is also the EU/ISO size, 46.8.
What is US 4 in UK ring sizes?
US 4 is a UK and Australian H½. UK letters step 1.25 mm of circumference at a time, so a half letter is a real difference.
What is US 4 in EU ring sizes?
US 4 is EU/ISO 46.8. The EU number is the inside circumference in millimeters, so a shop that stocks whole sizes will offer the nearest one.
What is US 4 in Japanese and Korean ring sizes?
US 4 is a Japanese and Korean 7. Those scales step a third of a millimeter of diameter per number, so they are finer than US half sizes.
Every ring size, US 3 to 13
Conversions are rounded to the nearest standard size, and published charts differ from each other by up to half a size. Treat the result as a close estimate, confirm it with a jeweler's sizer before buying, and check the resizing policy.