Ring Size Guide
Find your ring size in five minutes with things you already have at home. Pick one of the two methods below, then match your number to the size chart.
You'll need:
- A piece of string, dental floss or a thin strip of paper (about 1 cm wide)
- A pen
- A ruler with millimetres (check it starts exactly at 0)
- Or: a ring that already fits the finger you want to wear it on
Method 1: Measure your finger with string or paper
This gives you your finger's circumference — the distance around it — in millimetres.
- Cut a strip. Cut paper about 1 cm wide and 10 cm long, or use non-stretch string or dental floss. Stretchy string or wool will give you a size that's too small.
- Wrap it around the base of your finger. Use the finger and hand you'll wear the ring on. It should feel snug like a ring, not tight.
- Mark where it overlaps. Draw one thin pen line where the end meets the strip.
- Check the knuckle. Slide the loop off. If it won't pass your knuckle, loosen it slightly and mark again — the ring has to get over the knuckle.
- Lay it flat and measure. Measure from the end to your pen mark with a ruler, in millimetres.
- Find your size. Match the number to the Circumference column in the size chart below.
Method 2: Measure a ring you already own
This gives you the ring's inside diameter — the distance straight across the hole. It's the most reliable home method, and handy when buying a gift.
- Pick a ring that fits well. It must fit the same finger, on the same hand, you're buying for.
- Lay it flat on a ruler. Line up the inside edge of the ring with the zero mark.
- Measure across the middle. Read the distance from inside edge to inside edge, through the centre of the circle. Don't include the metal band.
- Find your size. Multiply your number by 3.14 to get the circumference, then match it to the Circumference column in the size chart below. For example, 16.5 mm × 3.14 = 51.8 mm, a US 6.
Tip: if your ring is a wide band, a thin ring in the same size will feel looser — see the tips below.
Ring size chart
Find the row closest to your measurement. If you land between two rows, choose the larger size.
| AU / UK | US | Circumference (mm) |
|---|---|---|
| H½ | 4 | 46.8 |
| I½ | 4½ | 48.0 |
| J½ | 5 | 49.3 |
| K½ | 5½ | 50.6 |
| L½ | 6 | 51.9 |
| M½ | 6½ | 53.1 |
| O | 7 | 54.4 |
| P | 7½ | 55.7 |
| Q | 8 | 57.0 |
| R | 8½ | 58.2 |
| S | 9 | 59.5 |
| T | 9½ | 60.8 |
| U | 10 | 62.1 |
| V | 10½ | 63.3 |
| W½ | 11 | 64.6 |
| X½ | 11½ | 65.9 |
| Y½ | 12 | 67.2 |
Millimetres follow the standard US sizing scale. Australia uses the same letter sizes as the UK.
Tips for an accurate fit
- Measure in the afternoon. Fingers are smaller in the morning and when cold, and swell after exercise, salty food or a hot day.
- Measure three times. Use the number that comes up most often.
- Use the right hand. Your dominant hand is often slightly bigger.
- Wide bands fit tighter. For a chunky ring (about 5 mm wide or more), go up half a size.
- Mind the knuckle. If your knuckle is much wider than the base of your finger, size for the knuckle so the ring slides on.
- A good fit goes on with a little push, comes off with a little twist, and doesn't spin around.
Still unsure?
I'm between two sizes. Go for the larger one. A slightly loose ring is comfortable; a tight one isn't.
I'm buying a gift. Borrow a ring they wear on the same finger and use Method 2. Or trace the inside of it on paper and measure the circle.
My measurements don't match. Measure again in the afternoon at room temperature, check you're using non-stretch string, and make sure your ruler or tape starts exactly at 0.
