Ring size calculator online

Find Your Ring Size

Measure your ring size at home and compare US/CA, UK/AU, IT/ES/CH, and RU sizes.

Online measurement is a guide, not a professional sizing guarantee. We recommend measuring 2–3 times or using a professional ring sizer before purchasing.

Method A

Measure an Existing Ring

First, calibrate your screen using a standard credit card or bank card (width: 85.60 mm). Adjust the bar below until it matches the width of your physical card held against the screen.

Calibrated

Please calibrate your screen first to enable the measurement circle.

Method B

Enter Finger Circumference

Wrap a thin strip of paper or string around your finger, mark where it overlaps, then measure the length in millimeters.

mm

International Ring Size Chart

Inside Diameter (mm) Inside Circumf. (mm) US/CA UK/AU IT/ES/CH RU

Tips for Accurate Measurement

  • Measure at the end of the day when fingers are usually slightly larger.
  • Avoid measuring when your hands are very cold.
  • Measure 2–3 times for a safer result.
  • Wider bands may feel tighter than thin bands.
  • Online measurement is a guide, not a professional sizing guarantee.
 

How to Use the Online Ring Size Calculator

Latoja’s free online ring size calculator helps you estimate your ring size at home using either a ring you already own or your finger circumference. You can then compare your estimated size across US/CA, UK/AU, and other international ring size systems.

Measure an Existing Ring

Choose a ring that fits the intended finger comfortably. Calibrate your screen with a standard credit card, then place the ring over the measurement circle and adjust it until the circle matches the inside edge of the ring. Measure only the inside diameter—do not include the metal band.

Measure Your Finger Without a Ring

Wrap a narrow strip of paper or a non-stretch string around the base of your finger. Mark where the ends overlap, lay it flat, and measure the length in millimeters. Enter this finger circumference into the calculator to find the closest estimated ring size.

Tips for Finding the Right Ring Size

  • Measure your finger two or three times for a more reliable result.
  • Measure near the end of the day, when your fingers are usually at their natural size.
  • Avoid measuring when your hands are unusually cold, hot, or swollen.
  • Make sure the paper fits securely without pressing tightly into the skin.
  • Check that the measured size can pass comfortably over your knuckle.

What If You Are Between Ring Sizes?

If your measurement falls between two sizes, the more comfortable choice depends on the ring design and your preferred fit. A wider band generally feels tighter than a narrow band, so some customers prefer the larger size. Rings with slim bands may feel comfortable in the closer size. If you are unsure, we recommend confirming the measurement with a professional ring sizer before ordering.

Are Men’s and Women’s Ring Sizes Measured Differently?

Men’s and women’s rings use the same ring size scale. The main differences are usually the average finger size and band width. Because many men’s wedding bands are wider, the same numerical size may feel tighter than it does in a narrow engagement ring.

How Accurate Is an Online Ring Size Calculator?

An online ring size calculator provides a useful estimate, but screen calibration, measuring pressure, finger temperature, knuckle width, and band design can affect the result. For the best accuracy, compare both measurement methods and repeat the process at different times of day. Online measurements should be used as a guide rather than a professional sizing guarantee.

Once you know your estimated size, explore Latoja’s engagement rings and bridal ring sets. If you need a size outside our standard options, visit Latoja Customization to discuss your ring requirements.