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At Class A Jewellers, all ring sizes are in Australian sizing. Australian sizing uses an alphabetical scale, where each letter corresponds to the ring's inner diameter and circumference.


For an accurate ring size, professional measurement is essential.

Visit our Walkerville showroom and our attentive staff will ensure your finger is measured precisely, no appointment necessary. 


Start by finding a ring that comfortably fits your intended finger. Using a ruler or tape measure, measure the internal diameter (in millimetres) of the ring, as precisely as possible. Then, refer to our Conversion Chart below for the size recommendation.


When it comes to purchasing an engagement ring, determining your partner's ring size can often be a challenging task. Here are some helpful suggestions that may assist you in discreetly finding their size, without ruining any surprises.

Find a Ring They Already Own

Our specialists can determine your partner's ring size by working backward from a ring they already own and wear. Ideally, choose a ring worn on their right ring finger (next to the pinky) for the closest fit. Keep in mind, if their dominant hand is their right, their left ring finger may be slightly smaller.

Ask a close friend or family member

It is likely that your partner’s best friend, parents, or sibling has bought them a ring before and knows their size. If not, they could discreetly find out. Enlist a close friend or family member on a mission to subtly ask or borrow one of their rings to measure.


Buy a loose gemstone

You could opt for a heartfelt approach and propose with a single diamond or gemstone, then join us to craft the ring together. This allows you to surprise your partner with a dazzling gem while adding a special touch of creating the ring together.

Go engagement ring shopping together

Make the experience memorable by going engagement ring shopping together. This eliminates the guesswork and allows you to discover your partner's preferences together. While browsing, have their ring professionally sized to ensure a perfect fit. Alternatively, suggest they shop with a close friend for their size and ring style preferences.


We understand the difficulty of selecting the correct size for your significant other’s engagement ring, which is why we offer complimentary resizing. All Class A rings are entitled to one complimentary resize within the first 12 months of purchase.*