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    Ring Size Chart & Finder

    Find your ring size with an at-home measurement guide and US/UK/EU conversion table.

    How to Measure

    1. Wrap a strip of paper or string around your finger
    2. Mark where the ends meet
    3. Lay it flat and measure the length in millimeters
    4. Divide by π (3.14) to get the inner diameter
    USUKEUDiameter (mm)
    3F4414.1
    3.5G4514.5
    4H46.514.9
    4.5I47.815.3
    5J4915.7
    5.5K50.316.1
    6L51.516.5
    6.5M52.816.9
    7N5417.3
    7.5O55.317.7
    8P56.618.1
    8.5Q57.818.5
    9R5918.9
    9.5S60.319.4
    10T61.619.8
    10.5U62.820.2
    11V6420.6
    11.5W65.321
    12X66.621.4
    13Z6922.2

    Tips for Accurate Sizing

    • Measure at the end of the day when fingers are slightly larger
    • Avoid measuring when hands are cold - fingers shrink in cold weather
    • Measure 3-4 times and take the average for best accuracy
    • If between sizes, go up - rings can always be sized down by a jeweler

    About This Tool

    This ring size conversion chart covers US, UK, EU, and metric (mm) sizing standards. Enter your measured inner diameter to instantly find your size across all systems. The chart covers sizes US 3 through US 13, which fits most adult ring sizes. For the most accurate fit, visit a jeweler for professional sizing.

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