Pearl sizing

Pearl size is the diameter of a single pearl in millimetres. It changes the look of a piece more than anything except length, and the price more than anything except grade. Here is how we measure, what each size looks like, and which to choose.

Our pearl sizes, side by side

Every strand and bracelet we sell comes in one of three sizes, and our studs run from 4 to 7 mm. The circles show how they compare.

US dime 17.9 mm, for scale
4 mm Dainty · our 3.5–4 mm strands
6 mm Classic stud · our 6–7 mm studs
8 mm Classic · our 7.5–8 mm strands
11 mm Statement · our 10.5–11 mm strands

Pearls and dime are drawn to the same scale as each other, not to life size.

How we measure

Across the widest point, to the nearest half millimetre.

Each pearl is measured with a caliper across its widest point. A strand is listed as a range, such as 7.5–8 mm, because no two pearls are identical: every pearl on the strand falls inside that range, and the range is never rounded up to sound bigger.

Half a millimetre matters more than it sounds. On a strand it is the difference between a necklace that reads as classic and one that starts to look substantial; a whole millimetre changes the character of the piece.

Which size to choose

Three strand sizes and a range of studs, each a different piece.

3.5–4 mm, dainty

A fine line of seed-sized pearls that reads almost like a chain. Made for layering and for every day, and the lightest strand to wear from morning to night.
7.5–8 mm, classic

The size most people picture when they think of a pearl necklace, and the one to choose if you are choosing once. It looks right at every length from choker to opera.
10.5–11 mm, statement

Large for a freshwater pearl, with real weight and presence across a room. Best at 18 inches or longer, where the bigger pearls have room to sit.
4–7 mm, studs

Earrings run smaller than strands: 4–5 mm for a first pair or a second piercing, 6–7 mm for the classic stud that covers the centre of the lobe.

Size and length

The same pearls look different at every length.

Small pearls suit shorter lengths, where they read as fine and modern; at opera length they read as a thread. Mid-size pearls look right at every length, which is why 7.5–8 mm at 18 inches is the usual first strand. Large pearls need room and look best from 18 inches down to the chest.

Our necklace length guide covers each length, the necklines it suits and how to measure.

Necklace lengths

Size and price

Price climbs faster than size.

Large, round, clean pearls are a small share of any harvest, so each step up in size is rarer than the one before, and the price of a strand rises much faster than its millimetres.

Grade still matters more than size. A well-graded 7.5–8 mm strand with sharp luster looks better than a larger strand with dull nacre, so choose the luster first and the size second.

How we grade

Sizing questions

What is the most popular pearl size?

7 to 8 mm. It is the classic size for a first strand and looks right at every length; ours is 7.5–8 mm.

Why is the size given as a range?

Because pearls are natural and no two are identical. Every pearl on the strand falls inside the stated range, measured across its widest point, and the range is never rounded up.

Do bigger pearls cost more?

Yes, and faster than the size suggests: large, round, clean pearls are a small share of any harvest, so each step up is rarer than the one before.

Which size is best for a bracelet?

7.5–8 mm matches a classic strand and suits most wrists. 3.5–4 mm is the dainty choice and 10.5–11 mm the bold one. Every bracelet page has a size guide for the wrist.

What size pearl earrings should I get?

4–5 mm for a small, everyday pair or a second piercing; 6–7 mm for the classic stud that covers the centre of the lobe.

See all questions