The Sizing Studio

How to find your ring size at home

Measure it in a minute — no guessing, no returns you didn’t want. Three honest ways to find your size, and a ruler you can trust before you trust the number.


Adjustable bands

Most of our rings have no size to choose

10 of our 11 rings are made on an adjustable band — the product page tells you which, and there is no size to select at checkout.

What we cannot tell you about an adjustable band: our maker states that these bands adjust, but does not publish the span they adjust across — and we are not going to invent one. If you are buying for yourself, an adjustable band is the most forgiving ring we sell. If you are buying for someone else and want certainty rather than likelihood, our earrings involve no fit at all, and every necklace and bracelet we make carries its adjustable range in millimetres on its own product page.

Wondering how a carat translates into millimetres on an ear? Every pair we sell, measured.

  • It is open at the back. The band is not a closed circle: the two ends of the shank pass each other, so it widens and narrows.
  • Ease it on, don’t lever it. Open it just enough to clear the knuckle, with gentle even pressure on both shoulders — the two sides of the band — never by twisting against the setting.
  • It holds the shape you set. Close it down onto the finger once and leave it there. Working a band open and shut every day is what tires metal.
Not sure it will fit you

Measure the base of the finger in millimetres — the three methods below show how — then send that reading to hello@maisonnoctaura.com and we will answer before you order.

Ring size

Three ways to measure a ring

Print at 100% (no scaling) on letter paper, then check the ruler below reads exactly its marks before you trust it.

Print the strip sizer

Print at actual size, cut the strip, wrap it around your finger and read where it meets. Calibrate with the ruler below first.

Measure a ring you own

Take a ring that already fits the right finger and measure its inner diameter in millimetres, edge to edge. Match it to the table below.

Wrap paper and mark it

Wrap a thin strip of paper snugly around the base of your finger, mark where it overlaps, then measure that length — the inner circumference.

Calibrate first Printed at 100%, this bar measures exactly 100 mm (10 cm). If a ruler laid against your print disagrees, set your printer to “Actual size / 100% / no scaling” and print again.

US ring size to millimetres — measured at the inner edge of the band.
US sizeInner diameterInner circumference
515.7 mm49.3 mm
616.5 mm51.8 mm
717.3 mm54.4 mm
818.1 mm56.9 mm
918.9 mm59.4 mm
1019.8 mm62.2 mm
A steadier fit

Between sizes? Size up. Measure at the end of the day, when fingers are largest, and take the reading two or three times. Cold hands read small.

Necklace length

Where each length falls

Choker · 14″
Sits high, close around the base of the neck.
Princess · 18″
The everyday drop, resting just below the collarbone.
Matinee · 20–24″
Falls onto the chest — layer it or wear it long.
Bracelet

A comfortable wrist

Wrap a strip of paper around your wrist where the bracelet will sit, mark the overlap, and measure it. Then add a finger’s width for ease so it moves without sliding off.

Still unsure

Want a second opinion before you order? The ring-size converter below turns a millimetre measurement into your US size in a moment — and you’re welcome to write to us with your reading and we’ll help you land on the right size.

Got your size? The pieces are waiting to be worn — and if this is for a proposal, our honest guide to moissanite engagement rings covers what to weigh before you choose.

The Atelier

Find your ring size

Your US size

7

A precise fit for US 7.

How to measure — wrap a thin strip of paper snugly around the base of the finger, mark exactly where it overlaps, then measure that length in millimetres. That length is the inside circumference. EU sizes shown are the ISO standard: the circumference in millimetres, rounded.

Most of our rings are on adjustable bands and have no size to choose — this converter is for the sized pieces, and for telling us your measurement.