How to find her ring size without asking.
A few quiet ways to find her ring size, from the most reliable to a careful guess, with a size chart in millimeters.
Start here: you need less than you think
Most people planning a proposal don't know her ring size. That's normal, and it doesn't stop you starting. A close estimate is enough to design around, and there are a few quiet ways to get one.
In order of how reliable they are:
- Measure a ring she already wears. The best option by far.
- Ask someone who knows. A sister, a close friend, her mother.
- Make an educated guess, then narrow it with someone who has done this before.
Measure a ring she already wears
Borrow a ring she wears often, ideally one she wears on her ring finger. Choose a time she won't miss it for an hour.
Then use any of these:
- Our ring sizer. Lay the ring flat on your screen and match the circle to its inside edge. It uses any bank card to calibrate your screen, so the measurement is real size, not a guess.
- A ruler. Measure straight across the inside of the band, edge to edge, in millimeters. Then find it in the table below.
- Trace it. Draw around the inside of the ring on paper with a sharp pencil. Measure the circle, or bring the tracing to your call.
- Press it into soap or clay. An old trick that still works: it keeps an exact impression you can measure later.
If the ring is from a different finger, note which one. Fingers on the dominant hand are often a little larger, and middle fingers are larger than ring fingers.
Ask someone who knows
Her sister, a close friend or her mother may know her size, or can find out without it seeming strange. Jewelry she has had resized before is another clue: the receipt or the jeweler may have it on record.
If you ask a friend, ask one who can keep a secret. The surprise is part of the gift.
If you have nothing to measure
Most women's ring sizes fall between about 5 and 7, with 6 among the most common. Height and build give a rough steer, not an answer: someone petite with slim hands is more likely to be a 4½ to 5½, someone tall is more likely to be a 6½ or above.
A few things make a guess better:
- Hold her hand and compare her ring finger with your own fingers. If her finger is close to your little finger, that's a useful reference.
- Notice whether her rings slide over her knuckle easily or need a twist. Knuckles matter as much as the base of the finger.
- If you're between two sizes, the slightly larger one is usually kinder: a ring that's a touch loose can be worn, one that's tight can't.
On a call, we'll help you narrow it down and tell you honestly how confident we are before anything is made.
US ring sizes in millimeters
Inside diameter is measured straight across the inside of the band. Sizes in between follow the same steps.
| US size | Inside diameter | US size | Inside diameter |
|---|---|---|---|
| 4 | 14.9 mm | 7 | 17.3 mm |
| 4½ | 15.3 mm | 7½ | 17.7 mm |
| 5 | 15.7 mm | 8 | 18.1 mm |
| 5½ | 16.1 mm | 8½ | 18.5 mm |
| 6 | 16.5 mm | 9 | 18.9 mm |
| 6½ | 16.9 mm |
Sizes are based on the US standard. Measurements this small are easy to misread by half a size, so measure twice.
If the size turns out to be wrong
Whether a ring can be resized later depends on its design. Plain bands are usually straightforward. Rings with stones set all the way around the band, or very fine settings, can be harder or not possible. That's why it's worth getting the size as close as you can before the ring is made, and why we talk it through on the call.
Questions
- What's the most common ring size for women?
- Most women wear a size between about 5 and 7, and 6 is among the most common. It varies a lot, so treat it as a starting point, not an answer.
- Is it better to guess too big or too small?
- Slightly large is usually better. A ring that is a touch loose can still be worn, while one that is too tight cannot go over the knuckle.
- Does her ring finger size change?
- A little. Fingers are slightly larger in the heat and later in the day, and smaller in the cold. A good fit slides over the knuckle with a little resistance and doesn’t spin.
- Can I measure her finger while she sleeps?
- People do, but string and paper strips around a finger are easy to get wrong, and the knuckle is easy to miss. Measuring a ring she already wears is far more reliable.
- Can an engagement ring be resized?
- Often, but it depends on the design. Plain bands are usually easy. Rings with stones all the way around the band can be difficult or not possible, which is why the size is worth getting right first.