My Ring Size Calculator

My Ring Size Calculator - Logo
Menu



Signet Ring Size Chart: MM, Inches, US, UK & EU Sizes + Free PDF


Signet Ring Size Chart: Sizes in MM, Inches, US, UK & EU

A signet ring size chart converts your finger measurement into a ring size. Signet rings use the same US, UK and EU sizes as other rings, but the flat top and wide band of many designs can make them fit tighter. Use the chart below to find your size, then read the fit tips for pinky, men’s and women’s signet rings.

Quick answer: a US size 7 signet ring has an inner diameter of 17.32 mm (0.682 in) and an inner circumference of 54.4 mm, which is UK N½ and EU 54. Measure your finger in mm, match it to the chart, and go up a quarter to a half size if the band is wide.
Get the printable signet ring size chartFree A4 PDF with a 100% print-scale check. No sign-up needed.

Download the Signet Ring Size Chart PDF

How Signet Rings Are Sized

A signet ring is a ring with a flat or slightly domed face, traditionally engraved with a crest, monogram or initials. It is sized exactly like any other ring: by the inside diameter or circumference of the band. The ISO 8653 standard defines ring size by inside circumference in millimetres; see the ring size overview for background.

What makes signet rings different is the fit. The face is wider than a plain band, and many signet rings are heavy or tapered, so a ring that matches your measurement on paper can still feel snug. Getting the finger and band width right matters as much as the number.

Signet Ring Size Conversion Chart (MM, Inches, US, UK, EU)

Inner diameter is the width across the inside of the band. Inner circumference is the distance around it. Highlighted rows are common reference points.

Signet ring size conversion chart, US sizes 3 to 13
Ring size (US) Inner diameter (mm) Inner diameter (in) Inner circumference (mm) US UK EU
3 14.07 0.554 44.2 3 F 44
3.5 14.47 0.570 45.5 3.5 G 45
4 14.88 0.586 46.8 4 H 47
4.5 15.29 0.602 48.0 4.5 I 48
5 15.69 0.618 49.3 5 J½ 49
5.5 16.10 0.634 50.6 5.5 K½ 51
6 16.51 0.650 51.9 6 L½ 52
6.5 16.91 0.666 53.1 6.5 M½ 53
7 17.32 0.682 54.4 7 N½ 54
7.5 17.73 0.698 55.7 7.5 O½ 56
8 18.13 0.714 57.0 8 P½ 57
8.5 18.54 0.730 58.2 8.5 Q½ 58
9 18.95 0.746 59.5 9 R½ 60
9.5 19.35 0.762 60.8 9.5 S½ 61
10 19.76 0.778 62.1 10 T½ 62
10.5 20.16 0.794 63.3 10.5 U½ 63
11 20.57 0.810 64.6 11 V½ 65
11.5 20.98 0.826 65.9 11.5 W½ 66
12 21.38 0.842 67.2 12 X½ 67
12.5 21.79 0.858 68.5 12.5 Z 68
13 22.20 0.874 69.7 13 Z½ 70

Formulas used: circumference = π × diameter; inches = mm ÷ 25.4; EU size = inner circumference in mm, rounded. UK letters are matched to the nearest published inner diameter. Sizes vary slightly by brand.

Pinky Signet Ring Sizes

The little finger is the traditional home of the signet ring. The pinky is usually narrower than the ring finger, and many people find it is roughly one to three sizes smaller, though this varies. Measure the pinky itself rather than guessing from your ring-finger size. Pinky signet rings often fall between about US 3 and US 8.

Pinky signet ring sizes: US 3 to 8
Ring size (US) Inner diameter (mm) Inner diameter (in) Inner circumference (mm) US UK EU
3 14.07 0.554 44.2 3 F 44
3.5 14.47 0.570 45.5 3.5 G 45
4 14.88 0.586 46.8 4 H 47
4.5 15.29 0.602 48.0 4.5 I 48
5 15.69 0.618 49.3 5 J½ 49
5.5 16.10 0.634 50.6 5.5 K½ 51
6 16.51 0.650 51.9 6 L½ 52
6.5 16.91 0.666 53.1 6.5 M½ 53
7 17.32 0.682 54.4 7 N½ 54
7.5 17.73 0.698 55.7 7.5 O½ 56
8 18.13 0.714 57.0 8 P½ 57

Women’s Signet Ring Sizes

Women’s signet rings are usually worn on the pinky or ring finger. Ring-finger sizes commonly fall between about US 5 and US 9. See also the women’s ring size chart.

Women’s signet ring sizes: US 5 to 9
Ring size (US) Inner diameter (mm) Inner diameter (in) Inner circumference (mm) US UK EU
5 15.69 0.618 49.3 5 J½ 49
5.5 16.10 0.634 50.6 5.5 K½ 51
6 16.51 0.650 51.9 6 L½ 52
6.5 16.91 0.666 53.1 6.5 M½ 53
7 17.32 0.682 54.4 7 N½ 54
7.5 17.73 0.698 55.7 7.5 O½ 56
8 18.13 0.714 57.0 8 P½ 57
8.5 18.54 0.730 58.2 8.5 Q½ 58
9 18.95 0.746 59.5 9 R½ 60

Men’s Signet Ring Sizes

Men’s signet rings are commonly bought in sizes from about US 8 to US 13 for the ring finger, and in smaller sizes for the pinky. Larger faces and thicker shanks fit more snugly, so consider going up a half size. See also the men’s ring size chart.

Men’s signet ring sizes: US 8 to 13
Ring size (US) Inner diameter (mm) Inner diameter (in) Inner circumference (mm) US UK EU
8 18.13 0.714 57.0 8 P½ 57
8.5 18.54 0.730 58.2 8.5 Q½ 58
9 18.95 0.746 59.5 9 R½ 60
9.5 19.35 0.762 60.8 9.5 S½ 61
10 19.76 0.778 62.1 10 T½ 62
10.5 20.16 0.794 63.3 10.5 U½ 63
11 20.57 0.810 64.6 11 V½ 65
11.5 20.98 0.826 65.9 11.5 W½ 66
12 21.38 0.842 67.2 12 X½ 67
12.5 21.79 0.858 68.5 12.5 Z 68
13 22.20 0.874 69.7 13 Z½ 70

Wide Bands and Flat Tops: Should You Size Up?

Narrow band versus wide flat-top signet bandOn the left a narrow band sits loosely on a finger; on the right a wide flat-top signet band covers more of the finger and fits tighter, so a half size up may be needed. Narrow bandLight contactTrue size usually fits Wide flat-top signetMore contact, feels tighterConsider a half size up
A wide, flat-top signet touches more of the finger, so it often feels tighter than a narrow band in the same size.

A wider band has more contact with the skin and is harder to slide over the knuckle. If you are between sizes, or the signet band is wide or heavy, many people choose a quarter to a half size larger. Always check the seller’s size notes and return policy, because shank shape and weight differ by maker.

Signet ring fit by finger
Finger How it compares Fit tip
Pinky Usually the smallest size, often one to three sizes under the ring finger Measure the pinky itself; the knuckle is smaller
Ring finger Your usual ring size Add a quarter to half size for a wide band
Index finger Often about one size larger than the ring finger Measure it separately, since hands vary

How to Measure Signet Ring Size in MM and Inches

Millimetres are the most accurate unit. Convert to inches by dividing by 25.4. Our how to measure your ring size guide and the ring size calculator cover more methods.

Measure an Existing Ring

Measuring the inner diameter of a signet ringA signet ring with a flat face seen from above, with a horizontal line across the inside edge to edge labelled inner diameter. Inner diameter 1. Measure inside edgeto inside edge, not theflat face or outer band. 2. Read it in mm.Inches = mm ÷ 25.4Example: 16.51 mm = 0.650 in
Measure the inside of the band edge to edge, away from the flat face.
  1. Choose a ring that fits the same finger comfortably.
  2. Lay it flat and measure the inside width at its widest point, in mm.
  3. Find the nearest value in the “Inner diameter (mm)” column.
  4. Multiply the diameter by 3.1416 to check the circumference.

Measure Finger Circumference with a Paper Strip

Measuring finger circumference with a paper stripA paper strip wrapped around a finger with a pen mark where the end overlaps, then laid flat against a ruler. 1. Wrap and mark 0mmmm Length 0 to mark = circumference 2. Lay flat and measure in mm
Wrap, mark, then measure the strip against a ruler.
  1. Cut a strip of paper about 10 mm wide and 150 mm long.
  2. Wrap it around the base of the finger you will wear the signet on and mark where it overlaps.
  3. Lay the strip flat and measure from the end to the mark in mm.
  4. Match the result to the “Inner circumference (mm)” column. Use string or a tape measure the same way.
Tip: measure at the end of the day when fingers are warm, and repeat three times. If your knuckle is larger than the base of your finger, choose a size that passes the knuckle.
Print the chart and check your sizeFree A4 PDF with a 100% print-scale check. No sign-up needed.

Download the Signet Ring Size Chart PDF

How to Choose the Right Signet Ring Size

  • Pick the finger first. Pinky, ring finger and index finger need different sizes.
  • Use millimetres. Compare your circumference with the chart and the seller’s size notes.
  • Check the band width. Wide bands and big faces feel tighter; go up a quarter to a half size if between sizes.
  • Check the knuckle. The ring must pass over it and still sit snugly.
  • Test the fit. It should turn with slight effort and not slip off when your hand is relaxed.

Can Signet Rings Be Resized?

Often, but ask a jeweller before you buy or alter one. Engraved faces, hallmarks, enamel and inset stones can limit resizing, and large changes can distort a flat top. Hollow or very thick shanks are harder to adjust. Related guides: US ring size chart, UK ring size chart and ring size conversion chart.

Signet Ring Size FAQs

What size is a signet ring?

There is no single signet ring size. Signet rings are made in the same US, UK and EU sizes as other rings. The size you need depends on the finger you wear it on: pinky signet rings are usually smaller than ring-finger signet rings.

What size is a men’s signet ring?

Men’s signet rings are commonly ordered between about US 8 and US 13 for the ring finger, and often a few sizes smaller for the pinky. Measure the finger you will wear it on rather than relying on a typical size.

What size pinky signet ring do I need?

Many people find their pinky is about one to three sizes smaller than their ring finger, but this varies from person to person. Measure your pinky circumference in millimetres and match it to the chart on this page.

Should I size up for a wide or flat-top signet ring?

Often yes. A wide band or a broad flat face covers more of the finger and tends to feel tighter than a thin band of the same size. If you are between sizes, many people go up a quarter to a half size. A jeweller or the seller’s size notes can confirm.

How do I measure my signet ring size at home?

Wrap a strip of paper around the base of your finger, mark the overlap and measure the length in millimetres. Match that circumference to the chart. You can also measure the inside diameter of a ring that already fits the same finger.

Can a signet ring be resized?

Often it can, but a jeweller has to check first. Engraving, hallmarks, enamel, inset stones and a hollow or very thick shank can limit how much a signet ring can be resized, and large changes may distort the face.

Which finger is a signet ring traditionally worn on?

Traditionally on the little finger of the non-dominant hand, though many people wear signet rings on the ring finger or index finger today. Choose the finger that suits you, then size for that finger.

Are signet ring sizes different from wedding ring sizes?

No. They use the same standard size scales. The difference is in the fit: the flat top and heavier build of many signet rings can make the same size feel tighter than a slim band.

Related Ring Size Guides

Download your free signet ring size chartFree A4 PDF with a 100% print-scale check. No sign-up needed.

Download the Signet Ring Size Chart PDF

Scroll to Top