Our story

Royal Coster Diamonds Size	MM / INCH (Circumference)
	48 / 1.89	48 4½ I½ 8
	49 / 1.93	49 4¾ J¾ 9
	50 / 1.97	50 5½ K 10
	51 / 2.01	51 5¾ L 11
	52 / 2.05	52 6 L½ 12
	53 / 2.09	53 6¼ M½ 13
	54 / 2.13	54 6¾ N½ 14
	55 / 2.17	55 7¼ O 15
	56 / 2.20	56 7½ P 16
	57 / 2.24	57 8 P½ 17
	58 / 2.28	58 8¼ Q½ 18
	59 / 2.31	59 8¾ R 19
	60 / 2.36	60 9 S 20

Royal Coster
Diamonds Size

MM / INCH (Circumference)

48 / 1.89

49 / 1.93

50 / 1.97

51 / 2.01

52 / 2.05

53 / 2.09

54 / 2.13

55 / 2.17

56 / 2.20

57 / 2.24

58 / 2.28

59 / 2.31

60 / 2.36

Discover your ring size
1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions. 2. Check which circle matches the size of your ring. Make sure that the black circle is only visible within the ring. 3. If the ring is in between two circles (sizes), we recommend the larger size.
1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions. Then, cut out the Finger Sizer. 2. Cut the small gold line. Wrap the sizer around the largest part of your finger and make sure it is tightened. 3. Read your ring size from the sizer. If your ring size is in between two circles (sizes), we recommend the larger size.

Discover your ring size

Measure an existing ring

Measure your finger

1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions.

2. Check which circle matches the size of your ring. Make sure that the black circle is only visible within the ring.

3. If the ring is in between two circles (sizes), we recommend the larger size.

1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions. Then, cut out the Finger Sizer.

2. Cut the small gold line. Wrap the sizer around the largest part of your finger and make sure it is tightened.

3. Read your ring size from the sizer. If your ring size is in between two circles (sizes), we recommend the larger size.

Our Legacy Of 180 Years Of Diamond Craftsmanship

The world’s oldest and most trusted diamond factory has a rich and compelling history. Royal Coster Diamonds is around for a long time, dating back all the way to at least 1840. Actually, Mr. Coster founded his company before that date, but we just cannot prove it. Therefore, we stick to what we do know. Let us tell you more about our eventful history. A few of our highlights are:

Blog posts

View all posts

Amsterdam; City of Diamonds

By Robert GrootSep 28, 2022

How did Amsterdam become the City of Diamonds? Amsterdam has been the City of Diamonds for more than 400 years. The story of how Amsterdam became the diamond capital of...

Brief History of Diamonds

By Robert GrootNov 3, 2020

In the hectic days of constant rushing around, the little sparkle of a diamond helps you pause for a second and forget about the worries of the world. Take that...

royal experience Royal Coster Diamonds, diamond tour, diamond factory

Visit royal coster

Book An Experience And Learn About Our Heritage Or Visit Us To See More Diamonds & Jewelry

Your location is set to United States

Change language

Your cart

Your cart is empty

Find Your Ring Size

Discover your ring size

Still not sure about your size?

Your Enquiry

Your Enquiry

DROP A HINT

Sender

Recipient

our story

Our Legacy Of 180 Years Of Diamond Craftsmanship

Blog posts

Amsterdam; City of Diamonds

Brief History of Diamonds

Visit royal coster

Availability