How to Measure Ring Size

Billions of people wear rings across many cultures around the world. There are various reasons people wear them– some for religious or cultural reasons, others as a sign of marriage/engagement, while some wear them as a fashion accessory. Whatever your reason for getting a ring, it’s essential to know how to measure the ring size that’s perfect for you.

Importance Of Ring Size Measurements

ring size

Until about ten months ago, I knew there were different ring sizes but never knew that there were standard ring size measurements. I found out the hard way when I was about to propose to my fiancee; I went to the jeweler to get an engagement ring, and the jeweler asked what ring size I wanted; “Wait, rings have sizes?” I asked.

I couldn’t find her ring size anymore because I wanted to keep the engagement a surprise and not arouse her suspicion. I bought a random “small” size, and the proposal went great… but the ring was so BIG that it awkwardly fell off her finger and even showed in the pictures we took. Thankfully, I changed the ring after the engagement at no added cost.

If you’re going to a jewelry store to buy a ring, you can test the rings until you find your size. However, as in my experience above, knowing ring size measurements is important to enabling you to buy rings without testing them. You might need to order a ring online or want to ask someone to buy one for you; knowing your ring size is important.

International Ring Size Measurement

The table below shows you the ring size in various regions worldwide and their conversions in diameter and circumference. You would use this table to get your appropriate ring size in the ring measurement methods below.

Note: The table below is measured in millimeters (mm); however, if you take your measurement using inches on your ruler, you can easily convert from mm to inches. To convert from mm to inches, multiply the number by 25.4; for example, 0.58 inches * 25.4 = 14.7 mm. Alternatively, you can use this online Unit Converter.

Circumference (mm)Diameter (mm)USUKEUROPE
14.946.84H 1/247
15.348.04.5I 1/248
15.749.35J 1/249
15.950.05.5K 1/250
16.551.96L 1/252
16.953.16.5M 1/253
17.354.47N 1/254
17.755.77.50 1/255
18.257.48P 1/257
18.558.38.5Q 1/258
19.059.59R 1/259
19.460.89.5S 1/261
19.862.110T 1/262
20.263.410.5U 1/263
20.765.111V 1/264
21.065.911.5W 1/266
21.467.212X 1/267
21.868.512.5Z68
22.269.713Z+170

Methods Of Measuring Ring Size

There are several ways you can measure the ring size that’ll perfectly suit you; I explain three methods below:

1. Use A Jeweler’s Sizing Tool

Ring size tool

Using a jeweler’s ring sizing tool is the most straightforward and accurate way to know your ring size. You can access these tools in most jewelry stores or stores with jewelry sections. In some cases, they might even allow you to try on various rings to see what fits, and you can find the size of the ring that fits and use that for future purchases.

You can also buy a plastic ring sizing tool for a lower price than the standard ones you’ll find in jewelry stores, and it works just as well. Ensure it isn’t too snug when measuring.

plastic ring sizing tool

2. Measuring Your Finger Size

You can find out the size of your ring by measuring the circumference of your finger and finding out what ring size matches it. You can measure your finger circumference with a string or a piece of paper.

A. Measuring Finger Size With A String

The string method is a simple one that won’t cost you a dime to use in measuring your ring size. To use this method, you need to get the following implements:

  1. A string that does not stretch, e.g., thread or floss.
  2. Marker or Scissors (optional)

You can use the string method alone or with some assistance from someone else.

Steps To Measure Finger Size With String

  1. Place the string around the knuckle of the finger that you want to wear the ring. Using the knuckle is more accurate than using the base of your finger because the finger base is usually smaller, and the ring might have difficulties passing your knuckles. 
    Ensure you do not squeeze too tightly for accurate measurement.
  2. If you’re doing it alone, take note of the beginning and end of the point where the two sides of the string meet.
    If there’s someone to assist you, let them cut the string on two ends at that point so it would remain only the strip that measures your finger around. Alternatively, they can use a marker to mark the point where the two ends of the thread meet.
  3. The string length from Point A to Point B is the circumference of your finger. Measure the circumference of your finger with a ruler; it’s easier and more accurate to use millimeters (mm), but you can also use inches.
  4. Check the table above to see what ring size corresponds to the circumference of your finger. 
    For example, if the circumference of your finger is 44.2 mm (1.74 in), you would need a size 3 ring in the US or a size 4 in Asia.

B. Measuring Finger Size With Paper

You can also measure your finger circumference easily with paper, a ruler, and a pen.

Steps To Measure Finger Size With Paper

  1. First, draw and cut out a piece of paper that looks like the shape below.
Image of Ring Size Measurement Paper
Ring Size Measurement Paper
  1. Use a ruler to draw the dimensions on the piece of paper pictured above in inches or millimeters.
  2. Tear a hole in the piece of paper at the Read Size point.
  3. Place the piece of paper on the knuckle of your finger. Insert the pointed end of the paper into the hole you tore at the Read Size point.
  4. Pull the paper till your knuckle fits perfectly with it.
  5. The last visible number on the piece of paper is the circumference of your finger.
  6. Check the table above to see what ring size corresponds to the circumference of your finger.
    For example, if the circumference of your finger is 46.8 mm (1.84 inches), you would need to get a size 4 ring in the US or a size 7 ring in Asia.

3. Measuring A Ring That Fits You Already

ring fitting

If you or anyone around you has a ring that fits you and you don’t know the size, you can measure it to find out your ring size. To measure your ring size using this method, you would need a ruler and the ring, then follow the steps below:

  1. Place the 0 mm (inch) end of the ruler on one end of the ring.
  2. Run the ruler across the middle of the ring; adjust the ruler until you get the largest width. The widest point of the ring is the measurement you need.
    The measurement of the ring across the middle is the diameter of the ring.
  3. Check the chart above to see what ring size would go with the diameter of your ring measurement.
    For example, if the diameter of your finger is 14.1 mm (0.5 inches), you would need a size 3 ring or a size 4 in Asia.

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