Finding Out Ring Size Without Asking: Five Methods That Really Work

You want to buy a ring – as a surprise. The problem is so classic that it would almost be funny if the solution weren't so important: you don't know the ring size, and you can't ask without ruining the surprise.

I've experienced this problem myself. I've researched, tried a few methods, and discarded a few others because they either don't work or are so obvious they'd ruin the surprise. What follows here are the methods that actually help.

Method 1: Briefly borrow one of her rings

The most reliable method, if feasible. If your partner, girlfriend, or whoever wears a ring – on any finger, not necessarily the ring finger – you can briefly take this ring, measure its inner diameter, and you'll have an exact size.

Measuring is done with a ruler on the inner diameter. Alternatively: place the ring on paper, trace the inner circle, measure the diameter. The inner diameter in millimeters is also the European ring size. A 17-millimeter diameter means size 53 to 54 (circumference in mm).

Important: Which finger counts? If you're buying a ring for the right ring finger – as is common in Germany for wedding rings and many other rings – then a ring she wears on her right ring finger is the best reference. A ring on the index finger is usually one size larger than the ring finger of the same hand.

Method 2: A piece of paper around the sleeping finger

Sounds like a scene from a bad movie, but it works. When she's asleep, you can wrap a narrow strip of paper around her ring finger, mark where it overlaps, and measure the length. This length is the circumference of the finger in millimeters – and that directly corresponds to the European ring size.

A finger with a circumference of 52 mm means ring size 52. You can then calculate back to the diameter: circumference divided by 3.14 gives the diameter in millimeters.

Method 3: Ask her best friend

Underestimated and effective. A best friend often knows this – either because they tried on rings together, because she knows the ring size, or because she agrees to discreetly find out. The advantage: no acting required, no risk of a sleeping finger.

If you choose this route: explicitly ask for discretion. And don't involve a whole group in the conspiracy – every additional person is another risk that the surprise will be spoiled.

Method 4: The standard size as a starting point

If none of the other methods are feasible, there's a statistical approximation. The average ring size for women in Germany is 54 to 56, for men 62 to 64. These numbers are not a guarantee, but as a starting point, they're better than blind guessing.

When in doubt: slightly larger is better than too small. Making a ring tighter is cheaper and easier (20 to 30 Euros at the goldsmith) than widening it, which can be difficult depending on the ring design.

Method 5: Simply accept that the first ring might not fit

This sounds like giving up, but it's actually the most relaxed solution. If you buy from a reputable seller with a 30-day return policy, then an incorrect ring size is not a drama – but a short detour.

You propose, the ring has its effect as a symbol, and then you both go for resizing or exchange. This takes the perfection out of the moment and instead gives her something else: the story of the ring you made right together.

What else I want to say

Ring size is important, but it's not the most important thing when buying a ring. More important is the material – whether the ring is made of real gold with a fineness stamp, so it lasts for the next few decades. And whether the design truly suits her, not just what you imagine.

At Corelune, there's a 30-day unconditional return policy – including size exchange for rings. Also, a downloadable printable measuring tape if you still want to find out the size before ordering. Because a well-fitting ring is more beautiful than one that has to go to the goldsmith after two weeks.