How to Measure Your Ring Size at Home
You don't need a jeweller to find your ring size. With a strip of paper or a piece of string and a ruler, you can measure accurately in about two minutes — then convert it to US, UK, EU or Japanese sizing below.
The string / paper method (step by step)
- 1 Wrap a strip of paper or string around your finger
Cut a thin strip of paper (about 1 cm wide) or use a piece of string. Wrap it snugly around the base of the finger you want to size — not too tight, not loose.
- 2 Mark where the ends overlap
Use a pen to mark the exact point where the strip meets itself. That overlap point marks your finger's circumference.
- 3 Measure the length in millimetres
Lay the strip flat against a ruler and read the length from the start to your mark, in millimetres. This is your inside circumference.
- 4 Convert the circumference to a ring size
Enter that millimetre measurement into the converter below to instantly get your US, UK, EU and Japanese ring size.
Convert your measurement to a ring size
Enter your circumference (mm) or the inside diameter of an existing ring:
Tip: wrap a strip of paper around your finger, mark where it overlaps, measure the length in mm = circumference.
Other ways to measure
- Measure a ring you own. Place a ring that fits over a ruler and measure the inside diameter in mm across the widest point. Most accurate if you have one.
- Use a printable ring sizer. Print our free ring sizer at 100% scale, then slide your rings over the circles to read the size directly.
- Visit a jeweller. For an engagement ring or a permanent purchase, a steel mandrel and sizing ring set at a jeweller is the gold standard.
FAQ
What is the best time of day to measure ring size?
Measure at the end of the day and when your hands are warm. Fingers are smallest in the morning and in cold weather, so a ring sized then may feel tight later.
How can I measure ring size with an existing ring?
Take a ring that already fits the right finger, measure its inside diameter in millimetres across the centre, and use our converter's diameter input. This is often the most accurate method.
Should the ring be tight or loose?
A well-fitting ring slides over the knuckle with slight resistance and sits comfortably. If your knuckle is much larger than the base of your finger, size to the knuckle so it can pass over.
How accurate is the string method?
Within about half a size when done carefully. String can stretch, so paper is slightly more reliable. For an expensive ring, confirm with a jeweller or our printable ring sizer.
Do wide bands need a different size?
Yes. Wide bands (6 mm or more) fit more snugly, so go up a quarter to a half size compared with a thin band.