Ring size is the single most common thing people get wrong, and it is also the easiest to fix — as long as you find out before the ring is made rather than after.

Here is how to measure properly at home, where home measuring goes wrong, and how to work out someone else’s size without spoiling a surprise.

Method 1: Measure a Ring She Already Wears

This is the most reliable home method by a wide margin, because you are measuring a known object rather than a finger.

Take a ring she already wears on the correct finger and measure the inside diameter across the widest point, in millimetres. A ring that measures about 16.5mm inside is roughly a US size 6; about 17.3mm is a 7; about 18.1mm is an 8. Those are approximations, not gospel, but they will land you within a size.

The critical part is the words “on the correct finger”. A ring she wears on her right middle finger tells you almost nothing about her left ring finger. Right hands are usually larger on right-handed people, and no two fingers match.

Method 2: String or Paper

Wrap a strip of paper or a piece of non-stretchy string around the base of the finger, mark where it overlaps, and measure the length in millimetres. Roughly 52mm is a size 6, 54mm a 7, 57mm an 8.

This works, but it is the method most likely to be off, for one reason: people pull it tight. The paper should sit the way a ring sits — snug, not compressing the skin.

The Four Things That Make Home Measurements Wrong

Knuckles. The ring has to pass over the knuckle and then sit comfortably at the base. If the knuckle is noticeably larger than the base of the finger, the correct size is a compromise and it genuinely needs fitting in person.

Temperature. Fingers swell in heat and shrink in cold, and the difference is often a full half size. Measuring on a hot afternoon or straight after exercise gives you a bigger reading than the truth. Measure at the end of a normal day at normal temperature.

Band width. A wide band fits more tightly than a narrow one at the same nominal size. If you measured with a thin band and are buying a 6mm band, you will usually want to go up a quarter to a half size.

Time of day and salt. Fingers are smallest in the morning and after a low-salt day. Anyone who has worn a ring for years knows it fits differently on different days — which is why “slightly loose” is a safer error than “slightly tight”.

How to Find Out Her Size Without Asking

The classics work:

  • Borrow a ring she wears on that finger for an evening and bring it to us. We can measure it in seconds.
  • Press one into soap or clay if you cannot take it out of the house. An impression of the inside is enough.
  • Ask her sister, her mother or her closest friend. Someone almost always knows, and they are usually delighted to be asked.
  • Bring the ring to us and we will size it exactly on a mandrel. This takes a minute and costs nothing.

What does not work well is guessing from how her hand looks, or using her shoe size, or any of the other folklore methods that circulate online.

If You Get It Wrong, It Is Not a Disaster

This is worth saying clearly, because people lose sleep over it: most rings can be resized. We do sizing on our own bench in Bakersfield, usually the same day, so a ring that is a size out after a proposal is a quick fix rather than a crisis.

There are exceptions, and they are worth knowing before you choose a ring:

  • Eternity bands set with stones all the way around cannot usually be sized, because there is nowhere to cut.
  • Tungsten, titanium and some other alternative metals cannot be sized at all — they have to be replaced.
  • Very thin or heavily worn bands may need building up before they can be sized safely.

If you are set on an eternity band, getting the size right the first time genuinely matters. For almost everything else, there is a safety net.

More on what sizing involves and what it costs: how much does ring resizing cost in Bakersfield?

Come In and Be Measured Properly

Thirty seconds with a proper ring sizer beats any amount of measuring with string. Both Bakersfield stores will size your finger for free, no appointment, whether or not you are buying anything that day — and if you are buying a wide band, we will size you with a wide sizer, which is the kind of detail that makes a ring comfortable for the next thirty years.

Rosedale Highway — (661) 587-9298
Ming Avenue — (661) 834-0824

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