MM → Inches
15.5 mm to inches
15.5 millimeters equals 0.610236 inches — or about 5/8" (nearest 1/16″).
Decimal
0.6102 in
Fraction
5/8"
Centimeters
1.55 cm
Feet
0.0509 ft
mm
0.610236
in≈ 5/8" (nearest 1/16)
1 in = 25.4 mm · tolerance ±0.0001
Formula
To convert mm to inches, divide by 25.4:
inches = mm ÷ 25.4
inches = 15.5 ÷ 25.4 = 0.610236
Why 15.5 mm = 0.6102 in
Since 1 inch is defined as exactly 25.4 millimeters, 15.5 mm converts to 0.610236 inches. Rounded to the nearest 1/16″ that's 5/8", which is what you'd read off a standard imperial ruler.