Home / Size Guides
Reference

Size & conversion charts

The tables product teams reach for when writing a specification. Sizes are stated to industry standard; we hold whatever you specify across the run.

Ring size conversion

USUKEUInside diameter (mm)Circumference (mm)
4H4714.946.8
54915.749.3
65216.551.9
75417.354.4
85718.157.0
95919.059.5
106219.862.1
116420.664.6
12Y6721.467.2
13Z+16922.269.7

Round brilliant — carat to millimetre

CaratDiameter (mm)
0.10 ct3.0 mm
0.25 ct4.1 mm
0.50 ct5.2 mm
0.75 ct5.8 mm
1.00 ct6.5 mm
1.50 ct7.4 mm
2.00 ct8.2 mm
3.00 ct9.4 mm
4.00 ct10.4 mm
5.00 ct11.2 mm

Necklace & bracelet lengths

TypeLengthSits at
Choker14–16 in / 36–41 cmBase of the neck
Princess17–19 in / 43–48 cmCollarbone
Matinee20–24 in / 51–61 cmTop of the bust
Opera28–36 in / 71–91 cmBelow the bust
Bracelet — S6.5 in / 16.5 cmSnug fit
Bracelet — M7 in / 17.8 cmStandard womens
Bracelet — L7.5 in / 19 cmLoose fit
Bracelet — Mens8–9 in / 20–23 cmStandard mens

Need a size run built into your programme?

Tell us the size distribution your market needs and we build it into the production plan.

Request a Quote