Skip to content
ringsizerchart

US ring size 5

A US size 5 ring is 15.69 mm (0.618") across the inside and 49.3 mm (1.94") round. It converts to UK J½, EU 49, Japan 9 and Swiss 9.5. The 1:1 circle below is already set to size 5: lay a ring on it to check yours.

Try

Lay a ring that fits flat on the circle and size the red line until it just touches the inside edge of the band all the way round: on a phone, slide sideways anywhere on the stage or hold the buttons below; on a computer, drag the edge, scroll or press ← →. The gold ring is the band’s wall: don’t match its outside.

US 515.69 mm · 0.618" inside · 49.3 mm round
Inside diameter15.69 mm
Band wall1.8 mm
Jump to US

Full chart 19 rows

Sort any column, download it as CSV or print it. Click a row to show it at 1:1.

Size 5 and the quarter sizes around it

9 rows
Download CSV
US ring size 5 and quarter sizes within one size either side: inside diameter, difference in mm, circumference, UK and EU sizes
Actions
14.88−0.81 mm46.8H½47
15.08−0.61 mm47.4I47
15.29−0.41 mm48.0I½48
15.49−0.20 mm48.7J49
15.69—49.3J½49
15.90+0.20 mm49.9K50
16.10+0.41 mm50.6K½51
16.30+0.61 mm51.2L51
16.51+0.81 mm51.9L½52

Ordering a size 5 in different band widths

4 rows
Download CSV
What size to order for a US size 5 finger in narrow, 4–6 mm, 7 mm and wider, and comfort-fit bands
Actions
515.69Bands under 4 mm usually fit true to size.
5¼–5½15.90–16.10A 4–6 mm band covers more skin and feels snugger: jewellers suggest a quarter to a half size up.
5½–616.10–16.51Wide and cigar bands grip the whole finger segment: half a size to a full size up.
4½–4¾15.29–15.49A domed comfort-fit inside slips over the knuckle more easily: often a quarter to a half size down.

Blank length for a size 5 band

6 rows
Download CSV
Length of wire or sheet to cut for a US size 5 ring band (15.69 mm inside) in stock 1.0 to 2.5 mm thick, by π × (inside diameter + thickness)
Actions
52.42.065"17.69
53.12.090"18.09
54.02.127"18.69
55.02.164"19.29
55.62.188"19.69
57.22.250"20.69

05 / Field guide

Size 5,
15.69 mm inside.

Everything about a US 5: what it measures, who usually wears it, how it converts in each country, the quarter sizes around it and what to order for wide bands. Neighbouring sheets: size 4½ and size 5½.

Who wears a size 5

A US 5 is a smaller women’s size, below the 6 to 8½ range most women wear, and a common pinky size for men. Jewellers’ order data puts the most common women’s size at 7 and men’s at 10, so a 5 is 2 sizes below the usual women’s size and 5 sizes below the usual men’s size. The same finger is often a quarter to half size larger on the dominant hand.

It is 0.41 mm wider inside than a 4½ (15.29 mm) and 0.41 mm narrower than a 5½ (16.10 mm). On the circumference that is 1.28 mm per half size, which is why a strip of string, stretching a couple of millimetres as you pull it snug, can misread a 5 by most of a size.

Size 5 in the UK, Europe and Japan

A 5 is 49.3 mm round. UK letters on the BS 6820 scale cover 0.625 mm each with half sizes, and J½ runs from 49.06 to 49.69 mm, so a 5 sits in the middle of J½. It converts cleanly, so a UK J½ ring should feel the same.

ISO 8653 rounds to the nearest millimetre, so EU 49 covers 48.5 to 49.5 mm and a 5 lands 0.80 mm into that band. Swiss and Italian sizes subtract 40, giving 9.5. Japan 9 is 15.7 mm inside, 0.01 mm larger than a US 5, so Japanese 9 is the nearest match.

Quarter sizes either side

A 4¾ is 15.49 mm and a 5¼ is 15.90 mm, each about 0.2 mm from a 5: roughly the thickness of two sheets of paper on the diameter. If your ring falls between 4¾ and 5¼ on the 1:1 circle, order a 5 for a band under 4 mm.

For a 4–6 mm band, jewellers suggest 5¼ to 5½; for 7 mm and wider, 5½ to 6; for a comfort-fit inside, 4½ to 4¾. Smart-ring kits that include a size 5 sample: Oura Ring 4, Galaxy Ring, Ring AIR.

Making a size 5 band

The blank length is the circumference of the middle of the band wall: π × (15.69 + thickness). Cut 54.0 mm of 1.5 mm stock or 55.6 mm of 2.0 mm stock, and the finished band has an outside diameter of 18.69 or 19.69 mm. Leave a little extra for filing the joint, and true the band on a mandrel at 5 after soldering.

Blank = π × (15.69 mm + t) · 1.5 mm → 54.0 mm · 2.0 mm → 55.6 mm

Questions

Answered plainly.

01What is a size 5 ring in mm?+

A US size 5 ring is 15.69 mm (0.618") across the inside, with an inside circumference of 49.3 mm (1.94").

02What is a US size 5 in UK and EU sizes?+

US 5 is UK J½ and EU (ISO 8653) 49. It is also Japan 9 and Swiss 9.5.

03How much bigger is a size 5½ than a size 5?+

A size 5½ is 0.41 mm wider inside (16.10 against 15.69 mm) and 1.28 mm longer round.

04How long a blank do I cut for a size 5 ring?+

54.0 mm for 1.5 mm thick stock and 55.6 mm for 2.0 mm, from π × (15.69 mm + thickness).

05Should I order a size 5 for a wide band?+

For a band 7 mm or wider, jewellers suggest 5½ to 6; for 4–6 mm, 5¼ to 5½. Under 4 mm, a 5 fits true to size.

Ring sizesUS · inside Ø mm

Carat sizes

Necklace lengths