Measure Ring Size

How to Measure Your Ring Size at Home with a Measure Tape – Riant Fine Jewelry Guide

Buying the perfect ring online starts with knowing your ring size—and doing it right at home is simpler than you think. With crafting custom jewelry with experiences of over a decade, I have seen the first hand that accurate measurements are happy with customers and low returns. Here is our fixed ring size guide, which is characterized by methods using a tape measurement, string, or an existing ring, as well as our official size chart.


 Why Accurate Ring Size Matters

  • A proper fit ensures your ring won’t fall off, yet slides comfortably over the knuckle.
  • Wide bands fit tighter—consider sizing up by half if the band is over 4 mm.
  • Temperature and time of day (like morning vs. evening) affect accuracy—fingers swell as the day progresses.


 Method 1: Measuring with a Tape Measure

What you need: flexible fabric tape measurement (tailor tape), pen, and perhaps a accessory.

  • Wrap the tape around the base of the finger where the ring will sit - to ensure that it can move to the knuckle.
  • Record the circumference in millimeters (eg 54 mm).
  • Use our size chart (bottom) to match our size shape.

Pro tips:

  • Measures at room temperature and mid-day.
  • Wrap snuggali - not tight - so the ring fits safely.
  • Measure 2-3 times for stability.


 Method 2: Using String or Paper

If you do not have a tape remedy:

  1. Wrap a non-stretch paper or a strip of string around your finger.
  2. Mark the overlap point.
  3. Measure the length marked with a ruler (in mm).
  4. Divide by 3.14 (π) to find diameter, then cross-refer our chart.
  5. If in the middle of the sizes, select the large size.


Method 3: Measure an Existing Ring

If you already have a well-fitting ring:

  1. Place the ring’s inner diameter over a ruler in millimeters.
  2. Consult the size chart to convert diameter to a US size.
  3. If unsure, choose the next nearest size up—for comfort and fit.


Riant Fine Jewelry Ring Size Chart (US Sizes)

US Size

Inner Circumference (mm)

Inner Diameter (mm)

5

49.5

15.7

5.5

50.5

16.1

6

51.9

16.5

6.5

52.8

16.9

7

54.4

17.3

7.5

55.2

17.7

8

56.8

18.2

8.5

57.6

18.5

9

59.1

18.9

For reference, the average women’s ring size is between 5 and 7, while men typically wear 10–11.


 Tips for a Perfect Fit

  • Measure in the evening when fingers are typically largest.
  • Avoid measuring in cold conditions, as fingers shrink slightly in chill.
  • Measure multiple times, across different days, for consistency.
  • Account for band width: wider ring = tighter fit; consider stepping up half a size.
  • Knuckle vs. base measurement: if knuckles are larger, use the larger measurement and choose size in between.


Measuring in Secret for Proposals

  • Borrow a ring she wears and use Methods 2 or 3—discreet and accurate.
  • Ask a friend or family member if they know her size.
  • Estimate using her average size and opt for slightly larger—rings can always be resized later.


Why Riant Fine Jewelry Offers Personalized Sizing Support

All Riant Fine Jewelry rings are created to US standard sizes. We offer free resizing within 30 days on most styles (excluding fully pave eternity bands). Our expert team is ready to advise on best-fit for your design and finger type.


Final Thoughts

Getting your ring size right is crucial for comfort, wearability, and long-term satisfaction. Whether using a tape measure, string, or an existing ring, you can accurately determine your size using our guide and size chart above.

Once you know your ring size, explore our stunning collections of loose diamonds, engagement rings, and custom jewelry at RiantFineJewelry.com with full confidence—and the perfect fit.

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