What you'll need: a thin strip of paper or piece of string, a pen, and a ruler.

1. Wrap the paper or string snugly around the base of the finger you plan to wear the ring on

2. Mark where the ends meet

3. Lay it flat and measure the length in millimetres — this is your finger circumference

4. Match that measurement to the chart below

A few tips for an accurate result:

• Measure at the end of the day when fingers are slightly larger

• Avoid measuring when your hands are cold or you've just exercised

• If your knuckle is wider than the base of your finger, measure both and choose a size between the two

• Measure the hand you intend to wear the ring on

If you already own a ring that fits the correct finger, place it on a flat surface and measure the internal diameter straight across the inside in millimetres. Match that number to the chart below.

The most reliable method is to be measured in person using professional ring sizers. Most jewellers offer this at no charge and it takes just a few minutes. We recommend this approach if you are between sizes or have larger knuckles.

Not knowing her ring size is completely normal — most engagement rings are bought this way. Here are a few ways to work it out discreetly:

Borrow a ring she already wears on the same finger of her right hand and measure the internal diameter

Ask someone close to her — a best friend or sister may already know

Make your best guess — the most common women's engagement ring size in Australia is between J and M

If the fit isn't perfect after the proposal, we offer professional resizing on most styles. Contact us and we'll take care of it.

Please note: some ring styles with pavé bands cannot be resized. This will be clearly stated on the individual product page.