Measuring ring size at home – three methods and a size chart
You can estimate your ring size at home using a well-fitting ring, finger circumference, or a ring sizer. Home measurement is indicative: the width of the ring, its shape, and fluctuations in finger size affect the final fit.
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Three ways to measure ring size at home
1. Measure the inner diameter of a suitable ring
Choose a round ring that fits well on the specific finger where you intend to wear the new ring. Measure from the inner edge to the opposite inner edge through the center. Do not include the thickness of the ring shank.
A caliper helps with precise measurement. It is easy to make a small error with a ruler. For example, an inner diameter of 17.0 mm corresponds to a size 17.0 based on diameter. Always check the sizing system used on the product page.
2. Measure finger circumference with a paper strip
Wrap a narrow, non-stretching strip of paper around your finger at the point where the ring will be worn. It should fit snugly, but not constrict. Mark the point where the ends overlap and measure the length in millimeters.
Also consider passing over the knuckle. Stretching the paper or measuring too tightly can distort the result. Convert the circumference using the table below; do not use the circumference figure as a diameter size.
3. Use a ring sizer and measure multiple times
A ring sizer helps to estimate the fit better than a single measurement with a ruler. Follow the instructions for the sizer and test it at different times of the day with your hand at normal temperature.
The width of the sizer does not necessarily correspond to the ring being purchased. Especially for wide rings or a stack of multiple rings, it is advisable to visit a store to try them on.
Ring size chart: diameter and circumference
The table converts inner diameter to circumference using the formula: circumference = π × diameter. The figures are rounded to one decimal place. They are not a universal size standard for all manufacturers.
| Inner diameter (mm) | Circumference (mm) |
|---|---|
| 15.0 | 47.1 |
| 15.5 | 48.7 |
| 16.0 | 50.3 |
| 16.5 | 51.8 |
| 17.0 | 53.4 |
| 17.5 | 55.0 |
| 18.0 | 56.5 |
| 18.5 | 58.1 |
| 19.0 | 59.7 |
| 19.5 | 61.3 |
| 20.0 | 62.8 |
| 20.5 | 64.4 |
| 21.0 | 66.0 |
| 21.5 | 67.5 |
| 22.0 | 69.1 |
| 22.5 | 70.7 |
| 23.0 | 72.3 |
Example: A circumference of about 55.0 mm corresponds to a diameter of about 17.5 mm. On the product page, the size may be stated as diameter, circumference, or a number from another sizing system. Check the notation before ordering.
How to check the ring's fit
- Snug but comfortable: The ring stays in place without feeling like it is pinching.
- Over the knuckle: The ring should be removable without excessive pulling, but it should not slide off by itself.
- Correct finger: Measure the exact finger and hand on which you intend to wear the ring.
- Width and shape: A wide ring or one with a different inner profile may feel like a different size. A general addition of 0.25–0.5 to the size does not replace trying it on.
- Multiple rings: Try on your engagement and wedding rings together if you plan to wear them side-by-side.
What if I'm unsure of the size?
Come and try on ring sizers in our store. If the ring is a surprise gift, a suitable ring worn by the recipient on the same finger can help with the estimation, but jewelry of a different width or worn on a different finger does not guarantee the correct size.
Resizing is possible for many rings, but it is assessed on a product-by-product basis. Read about ring resizing (enlarging) and reducing. Before ordering, also check the product's and store's current exchange and return policies, especially for rings that are engraved or made to order.
Help with your jewelry in Helsinki and Vantaa
Kulta-Aika Kamppi
Kamppi Shopping Center, 2nd floor
Urho Kekkosen katu 1
044 740 3800
kamppi@kulta-aika.com
Kulta-Aika Tammisto
Säätökuja 2B, Vantaa
044 740 3826
tammisto@kulta-aika.com
See store locations and opening hours · Explore goldsmith services
Frequently asked questions about ring size
Is ring size 17 the same as a circumference of 17 mm?
No. A diameter size of 17 refers to an inner diameter of about 17 mm, which has a circumference of approximately 53.4 mm. Check the sizing system used on the product page.
Which size should I choose if the measurement falls between two sizes?
The measurement figure alone does not determine the choice. The width of the ring, its shape, and the size of your knuckle affect the fit. Try on the options or ask for help before ordering.
Can I rely on paper measurement?
It provides an indicative estimate. The tightness of the strip and the point of measurement can change the result. Repeat the measurement and confirm an uncertain size by trying on a sizer.
Can a ring that is too large always be reduced?
Not always. Material, structure, and stone settings can limit resizing. Verify the possibility for the specifically chosen model.
Continue to selection: Women's engagement rings · Men's engagement rings · Ring compatibility guide.