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1/2 inch to decimal

The exact decimal value of 1/2 of an inch, with millimetres, centimetres and decimal feet — the numbers a tape or a caliper actually shows.

1/2 inch =

=0.5 in

Decimal inch

0.5"

Millimetres

12.7 mm

Centimetres

1.27 cm

Decimal feet

0.041667 ft

How it's figured

1 ÷ 2

A fraction of an inch is just the top number divided by the bottom: 1 ÷ 2 = 0.5". For metric, one inch is exactly 25.4 mm, so 0.5" × 25.4 = 12.7 mm. TapeMath keeps this exact as a fraction internally, so it never drifts the way a rounded decimal can.

Fractions nearby

The steps around 1/2"

Fraction	Decimal inch	Millimetres
29/64"	0.453125	11.50938 mm
15/32"	0.46875	11.90625 mm
31/64"	0.484375	12.30312 mm
1/2"	0.5	12.7 mm
33/64"	0.515625	13.09688 mm
17/32"	0.53125	13.49375 mm
35/64"	0.546875	13.89062 mm

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