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1/4 inch to decimal

The exact decimal value of 1/4 of an inch, with millimetres, centimetres and decimal feet — the numbers a tape or a caliper actually shows.

1/4 inch =

=0.25 in

Decimal inch

0.25"

Millimetres

6.35 mm

Centimetres

0.635 cm

Decimal feet

0.020833 ft

How it's figured

1 ÷ 4

A fraction of an inch is just the top number divided by the bottom: 1 ÷ 4 = 0.25". For metric, one inch is exactly 25.4 mm, so 0.25" × 25.4 = 6.35 mm. TapeMath keeps this exact as a fraction internally, so it never drifts the way a rounded decimal can.

Fractions nearby

The steps around 1/4"

Fraction	Decimal inch	Millimetres
13/64"	0.203125	5.159375 mm
7/32"	0.21875	5.55625 mm
15/64"	0.234375	5.953125 mm
1/4"	0.25	6.35 mm
17/64"	0.265625	6.746875 mm
9/32"	0.28125	7.14375 mm
19/64"	0.296875	7.540625 mm

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