Brand chart · United States
Blue Nile ring size chart
Blue Nile sells on the US numeric scale, mostly in half sizes. Because it is an online-first retailer, the size you type is the size that arrives — which makes measuring properly before ordering worth the extra minute.
The table
Blue Nile sizes in millimetres
Blue Nile quotes the us / canada numeric scale. A number from about 2 to 15 in half and quarter steps. Each whole size adds 2.5535 mm of inside circumference, so the scale is a straight line.
| Blue Nile size | Ø mm | Circ. mm | UK / AU | EU / ISO | India | Japan |
|---|---|---|---|---|---|---|
| 4 | 14.9 | 46.8 | H | 47 | 7 | #6 |
| 4½ | 15.3 | 48.0 | I | 48 | 8 | #8 |
| 5 | 15.7 | 49.3 | J | 49 | 9 | #9 |
| 5½ | 16.1 | 50.6 | K | 51 | 11 | #10 |
| 6 | 16.5 | 51.9 | L | 52 | 12 | #11 |
| 6½ | 16.9 | 53.1 | M | 53 | 13 | #13 |
| 7 | 17.3 | 54.4 | N | 54 | 14 | #14 |
| 7½ | 17.7 | 55.7 | O | 56 | 15 | #15 |
| 8 | 18.1 | 57.0 | P | 57 | 17 | #16 |
| 8½ | 18.5 | 58.2 | Q | 58 | 18 | #17 |
| 9 | 18.9 | 59.5 | R | 60 | 19 | #18 |
| 9½ | 19.4 | 60.8 | S | 61 | 21 | #19 |
| 10 | 19.8 | 62.1 | T | 62 | 22 | #21 |
| 10½ | 20.2 | 63.3 | U | 63 | 23 | #22 |
| 11 | 20.6 | 64.6 | V | 65 | 25 | #23 |
| 11½ | 21.0 | 65.9 | W | 66 | 26 | #24 |
| 12 | 21.4 | 67.2 | X | 67 | 27 | #25 |
| 12½ | 21.8 | 68.5 | Y | 68 | 28 | #27 |
| 13 | 22.2 | 69.7 | Z | 70 | 30 | #28 |
Derived from ISO 8653, the standard the whole trade sizes against, and labelled with the scale Blue Nile prints. It is a conversion table, not a copy of the brand's own list — confirm the exact range against the retailer before ordering, since any house can change what it stocks.
Sizing an order you cannot try on
Buying online removes the mandrel from the process, so the measurement has to carry the whole decision. Measure a ring that already fits on the correct finger, on its inside diameter, and take the reading twice on different days before committing.
Blue Nile and most online jewellers will mail a plastic or paper sizer free. Use it if the timing allows; use a printable ring sizer if it does not, checking the printed calibration bar against a bank card so you know the print scale came out right.
Returns and resizing
The cost of a wrong size online is time rather than money if there is a resizing or return window, but not every setting can be resized — eternity and channel-set bands typically cannot. Check the specific setting’s policy before you choose a size, not after.
If you are between sizes, order up. The calibrated ring sizer gives you the inside diameter in millimetres, which is the one number that means the same thing in every catalogue.
Before you order
What moves the size on a Blue Nile ring
- No mandrel in the loop
- Online orders rest entirely on your measurement. Take it twice, on different days, at room temperature.
- Print scale is the usual failure
- A printed sizer scaled to 97% is a whole size out. Always check the printed bar against a bank card.
- Not every setting resizes
- Eternity and channel-set bands generally cannot be adjusted. Confirm before choosing.
Ordering from elsewhere
Your size in the market you are buying from
The us / canada numeric scale is read in United States, Canada, Singapore, Malaysia, United Arab Emirates. Pick where you are ordering from and the switcher gives the local number for the same finger — or the millimetre, where local practice is too mixed to convert into.
Do not know it? Measure a ring on your calibrated screen — it is the only number here that is not a conversion of another number.
Indian numeric
14
A number from 1 to about 30. Indian jewellers frequently print the UK letter beside it, because both are in daily use.
India. Indian jewellers quote a numeric scale of their own, roughly 1 to 30. Tanishq, Malabar Gold, Kalyan and GIVA all use it, and many print the UK letter beside it. Online-first brands often list US sizes as well, so check which scale a listing means before ordering. Full India ring size chart.
United States. The US numeric scale, sold mostly in half sizes. Quarter sizes exist and a jeweller can cut them, but they are rarely stocked. Full USA ring size chart.
United Kingdom. Letters, in half-letter steps. British hallmarked rings are usually stamped with the letter, so an inherited ring often tells you its own size if you look inside the band. Full UK ring size chart.
Europe. France, Germany, the Netherlands and Scandinavia quote the ISO 8653 number, which is the inside circumference in millimetres. Italy, Spain and Switzerland quote the same measurement minus 40, so a 54 becomes a 14. Full Europe ring size chart.
Japan. The Japanese numeric scale runs #1 to about #27 for the sizes people actually order. Mikimoto, Tasaki and 4°C all use it. Japanese sizes are usually whole numbers only. Full Japan ring size chart.
China. Mainland Chinese listings usually give 圈号 — the inside circumference in millimetres, the same number as EU/ISO. Hong Kong uses a separate numbered scale, and marketplace listings mix both with US sizes. Order by inside diameter in millimetres when a listing does not say which scale it means.
Australia. Australia and New Zealand use the UK letter scale unchanged, so a UK N is an Australian N.
Canada. Identical to the United States. A US 7 is a Canadian 7, with no conversion in between.
Singapore. Singapore retail is mixed: international brands quote US numbers, goldsmiths in the Chinese tradition quote Hong Kong numbers, and British-founded chains quote letters. Ask for the inside diameter in millimetres and you sidestep the whole problem.
Malaysia. As in Singapore, US numbers dominate modern retail while traditional goldsmiths use Hong Kong numbers. Confirm the scale, or the diameter, before you order.
United Arab Emirates. Gulf retail quotes US sizes most often. British-founded chains use letters, and the many Indian gold houses in Dubai use the Indian scale, so the same finger can be quoted three ways along one street.
South Africa. South Africa follows the UK letter scale. Online stores that ship from the United States will quote numbers instead.
Brazil. Brazilian sizes are the inside circumference in millimetres minus 40 — the same arithmetic Switzerland uses. A 54 mm circumference is a Brazilian 14.
Mexico. Mexican jewellers use a local numeric scale that is not the US one, and the published conversions for it disagree with each other. We will not print a number we cannot stand behind, so order by inside diameter in millimetres, or ask the retailer for the diameter of the size they are offering. Large chains and online stores generally quote US sizes.
Questions
Blue Nile sizing, answered
What ring sizes does Blue Nile offer?
The US numeric scale, roughly 4 to 13 in half sizes, with some settings available in a narrower band.
How do I measure my ring size for an online order?
Measure the inside diameter of a ring that already fits, using a caliper or a calibrated screen, and convert with the table above. Measuring a ring beats measuring a finger because the ring has one fixed diameter.
Is a printed ring sizer accurate?
Only if it printed at exactly 100%. Check the calibration bar on the sheet against a bank card — ISO/IEC 7810 makes every card 85.60 mm wide — before trusting the circles.
Should I size up for a wide band?
Yes. Add half a size from about 5 mm of band width and a full size from about 9 mm.
Measure once, order in any scale
The sizer calibrates your screen against a bank card first, so the circle you match your ring to is a real millimetre wide.