Ring sizes in mm: chart and how to measure
A ring size from a Chinese seller is roughly the ring's inner circumference in millimetres minus 40: size 12 fits a finger of about 52 mm around, size 16 about 56 mm. Ring size numbers in Indonesia differ from shop to shop, so what you can rely on is your finger's circumference in millimetres.
How to measure your ring size
There are two ways to do it at home. Measure the finger the ring will go on, since your left and right hands can differ.
Measure your finger:
- Wrap a piece of thread or a thin strip of paper that doesn't stretch around the base of the finger.
- Mark where it meets with a pen.
- Lay it flat and measure it with a ruler in millimetres. That is your finger's circumference.
Measure a ring that fits:
- Put the ring on a ruler.
- Measure across the inside at the widest point, inner edge to inner edge. That is the inner diameter.
- Match it to the diameter column in the chart below.
Tips for a good fit:
- If your knuckle is wider than the base of your finger, measure over the knuckle so the ring will go on.
- Don't measure with cold hands. Fingers shrink in the cold and swell in the heat.
- Wrap the thread snugly, neither tight nor loose. A 1 mm difference is already one size.
Chinese ring size chart in mm
Sizes 4 to 26 are used by jewellery sellers in China (often called Hong Kong sizes, 港码). Circumference and diameter are measured inside the ring.
| Size (号) | Inner circumference (mm) | Inner diameter (mm) |
|---|---|---|
| 6 | 46 | 14.6 |
| 7 | 47 | 15 |
| 8 | 48 | 15.3 |
| 9 | 49 | 15.6 |
| 10 | 50 | 15.9 |
| 11 | 51 | 16.2 |
| 12 | 52 | 16.6 |
| 13 | 53 | 16.9 |
| 14 | 54 | 17.2 |
| 15 | 55 | 17.5 |
| 16 | 56 | 17.8 |
| 17 | 57 | 18.1 |
| 18 | 58 | 18.5 |
| 19 | 59 | 18.8 |
| 20 | 60 | 19.1 |
| 21 | 61 | 19.4 |
| 22 | 62 | 19.7 |
This chart is approximate. Some sellers use their own chart, half a size to a full size off, so if the seller gives a circumference or diameter, go by that.
Indonesian, US and Chinese ring sizes are not the same
The same number can mean a different circumference:
- Chinese / Hong Kong size: inner circumference (mm) minus about 40.
- US size: inner circumference (mm) = 2.55 × size + 36.5. US 6 is about 51.8 mm, US 7 about 54.4 mm.
- International size (ISO 8653): the number is the inner circumference in millimetres, so size 52 means 52 mm.
- Jewellery shops in Indonesia: each shop may use its own chart. If you know your number from a shop, ask for the circumference or diameter in millimetres too.
So a size 12 from a shop in Indonesia is not necessarily a 12号 in China. Compare millimetres, not numbers.
Words on a Chinese ring size chart
| Text | Meaning |
|---|---|
| 戒圈 / 圈号 | Ring size |
| 号 / 港码 | Size number (Hong Kong size) |
| 内周长 / 周长 | Inner circumference |
| 内直径 / 直径 | Inner diameter |
| 开口 / 活口 | Open ring, adjustable |
| 可调节 | Adjustable |
| 指围 | Finger circumference |
An open ring (开口 or 可调节) can be made a little smaller or larger, so the size doesn't have to be exact.
Choosing a ring size on Singaya
On Singaya's item pages, ring sizes appear as options, and we buy exactly the size you pick (choosing options). Before you choose:
- Check the description and photos. The seller's size chart is often in one of the photos.
- Match your finger's circumference or diameter to the seller's chart, not just the number.
- If you fall between two sizes, pick the larger one, especially for wide bands.
For clothes and shoes, see clothing sizes from China and shoe sizes from China in cm. Buying from China for the first time? Read how to buy goods from China for delivery in Indonesia.