Free Jewellery Hack- how to Figure out your ring size


Are you having trouble figuring out your ring size? The Good Opal co. are here to help.

The Good Opal co. is committed to helping our customers and providing the best customer service experience we can. That’s why once a week we write blogs like this, to help you, our customers by providing you with helpful information to make informed purchases. So, shop with confidence and if you can’t find what you’re looking for or have a custom design itch your wanting to scratch, contact me! All opals are available for any customisable jewellery design you can put your mind to, so you can find the perfect one of a kind piece for you.

So, to figure out your size for your custom ring we have listed below a few methods that you can use to determine your accurate size. If you’re still have trouble though, don’t worry, we are here to help and are contactable at

Or alternatively you can buy a ring sizer from

There are a few methods to figuring out your size.

You can you an existing ring you have, and convert it to the numbering standard of the chart listed below.

You can go by Diameter:
Diameter is the measurement across the inner width of a ring, going from one side to the other.

You’ll need:

  • Tape measure or ruler
  • A ring that fits you

Step 1:

Make sure the ring you’re using fits the finger you plan to wear it on.

Step 2: Using your ruler or tape measure, measure the widest points inside the ring from edge to edge.

If your ring is a different shape and is not circular, measure the shortest distance across.

Using the diameter measurement you’ve just found, consult the chart to see which size corresponds with your measurement.

14 mm3f1/244
14.6 mm3.75h46
15.3 mm4.5h1/2 – i1/248
16 mm5j-k50
16.5 mm6l – l1/252
17.2 mm7m1/2 – n1/254
17.8 mm7.5o – p56
18.5 mm8.5p1/2 – q1/258
19 mm9r1/2 – s60
19.8 mm10t1/262
20.4 mm10.5v64
chart source:

Helpful Sizing Tips:

When choosing your size:

Always choose the size of the largest finger on which you’ll be wearing the ring.


For a more comfortable fit, consider going one size up from your normal size.

Wide Shank:

If the ring has a wider shank, so we recommend going one size up from your normal size.

OR you can measure by circumference…

Circumference is the measurement around the base of the finger.

You’ll need:

  • String or strip of paper
  • Pen or marker
  • Tape measure or ruler

Step 1: Wrap a string comfortably around the desired finger.

Step 2: With the pen or marker, mark the spot where the string or paper meets and feels comfortable.

Step 3: Lay the string or strip of paper on a flat surface and measure its length in millimetres. This number is your finger’s circumference.

Using the circumference you’ve just found, consult the chart to see which ring size corresponds with your measurement.

44 mm3f1/244
46 mm3.75h46
48 mm4.5h1/2 – i1/248
50 mm5j-k50
52 mm6l – l1/252
54 mm7m1/2 – n1/254
56 mm7.5o – p56
58 mm8.5p1/2 – q1/258
60 mm9r1/2 – s60
62 mm10t1/262
64 mm10.5v64
Ring size chart

So, that’s all there is to it. Just remember at The Good Opal co., we are committed to sourcing all materials ethically, only sourcing the best quality Opal that doesn’t cost the Earth to sell to you. When you shop with The Good Opal co. you can rest assured that all opals and jewellery have been personally hand crafted from start to finished by me, because above all else we care about quality and Australian Opal!