A ring that is half a size too small will not go on. A ring that is half a size too big will come off in a coat pocket and never be seen again. Neither is a problem you want to solve by post, so it is worth ten minutes with a strip of paper before you order.
Method 1: measure a ring you already own (most accurate)
This is the best method by a wide margin, because it measures the space the finger actually occupies rather than the finger itself.
- Take a ring that fits the correct finger comfortably.
- Lay a ruler across the inside of the band and measure the widest inner distance in millimetres. Measure twice; a ring is rarely perfectly round.
- Match that inner diameter to the chart below.
US ring size chart
- Size 4 — 14.9 mm inner diameter — 46.8 mm circumference
- Size 5 — 15.7 mm — 49.3 mm
- Size 6 — 16.5 mm — 51.9 mm
- Size 7 — 17.3 mm — 54.4 mm
- Size 8 — 18.1 mm — 57.0 mm
- Size 9 — 19.0 mm — 59.5 mm
- Size 10 — 19.8 mm — 62.1 mm
- Size 11 — 20.6 mm — 64.6 mm
- Size 12 — 21.4 mm — 67.2 mm
- Size 13 — 22.2 mm — 69.7 mm
Half sizes fall exactly between the rows: each full US size is about 0.8 mm of diameter, so a half size is about 0.4 mm. That is small enough that a sloppy measurement will land you on the wrong one — hence measuring twice.
Method 2: the paper strip
If you have no ring to copy, measure the finger. Use paper, not string: string stretches and will read a size too large.
- Cut a strip of paper about 5 mm wide and 100 mm long.
- Wrap it around the base of the finger, snug but not tight — it should be firm enough that you have to work slightly to pull it off over the knuckle.
- Mark where the strip overlaps, unwrap it, and measure to the mark in millimetres. That is your circumference.
- Read the circumference column in the chart above.
If the knuckle is noticeably wider than the base of the finger, measure both and pick a size between the two. A ring has to pass the knuckle to get on, but it should not spin freely once it is on.
Five things that change the answer
Time of day. Fingers are smallest in the morning and largest at the end of a warm afternoon. Measure late in the day, at normal room temperature, and the ring will fit for most of the time you wear it.
Temperature. Cold fingers can measure a full size smaller. Do not size a ring straight after coming in from the cold, and do not size one after exercise either.
Which hand. For most right-handed people the right hand runs about a quarter to a half size larger. Size for the hand the ring will live on.
Band width. A wide band — anything over about 6 mm — occupies more of the finger and feels tighter than a narrow one at the same nominal size. For a wide band, go up a half size.
Season and health. Fingers swell in summer heat, in pregnancy, on long flights, and with some medications. If any of these apply, size for the larger state; a slightly loose ring can be worn, a tight one cannot.
What not to do
- Do not use a printable paper ring sizer unless you have checked the print scale with a ruler. Browsers and printers resize pages silently, and a chart printed at 96% will send you a size out.
- Do not size over a knuckle that is swollen from an injury or arthritis flare. Wait.
- Do not guess from a partner’s glove size or height. There is no reliable relationship.
If you are buying a surprise gift, the honest advice is to borrow one of their rings for an hour and measure it. Failing that, US size 7 is the most common women’s size and size 10 the most common men’s — but treat those as a coin toss, not a measurement.
How our listings work
Every ring on Rawkology states the US size it ships in, and where the manufacturer publishes it, the band width in millimetres. We stock fixed sizes; we do not resize rings, and neither we nor the manufacturer offer a resizing service, so the size on the listing is the size that arrives.
That makes the return window the safety net. You have 30 days from the day FedEx confirms delivery to send a ring back, and the terms are set out in full on our returns and refunds page. If you would like us to physically measure a ring in the warehouse before you order, email support@rawkology.com and we will.
