Inch Fraction Calculator

Convert inch fractions to decimal, convert decimal to inch fractions, convert inches to metric measurements, convert metric measurements to inch fractions, and convert to feet automatically.

Calculating inches, inch fractions, feet and centimeters

Inch Fraction, Decimal, and Metric Results

Imperial Units



Metric Units



Inch Fraction to Decimal Conversions

The chart below can be used to easily find the correct fraction for your decimal measurement, or vice-versa. Find decimal equivalents in 164” increments, including 12“, 14“, 18“, and 116“, and 132” measurements. The chart also shows hints on the markings sizes found on a tape measure or ruler.
Inch fraction to decimal inches conversion chart displays the decimal values for inch fractions in quarter inch, eight inch, thirty-second inch, and sixty-fourth inch increments

How to Calculate Inch Fractions

Inch fractions use denominators that are powers of 2 and go up to the 64th of an inch. That means the fraction denominators will be 2, 4, 8, 16, 32, and 64. This means that converting a decimal to an inch fraction is not as simple as finding the nearest fraction. Instead, it is necessary to find the nearest fraction with the denominator that is a power of 2. Typical inch fractions will look something like 1/64, 1/32, 1/16, 1/8, 1/4, or 1/2.

Finding Inch Fractions on a Tape Measure

Inch fractions on a tape measure are distinguished by the size of the tick mark

Finding measurements on a ruler or tape measure can be confusing at first, but once you understand how the marks are laid out then it is far simpler. The markings between the larger inch numbers vary in length.

The longest markings will be the quarter inch markings, ie. the first marking is 1/4 inch, the second is 1/2 (2/4) inch, the third is 3/4 inch.

The next longest markings will be the eight inch markings, ie. the first marking is 1/8 inch, the second is 3/8 inch, the third is 5/8 inch, etc.

The next longest markings will be the sixteenth inch markings, ie. the first marking is 1/16 inch, the second is 3/16 inch, the third is 5/16 inch, etc.

Find inch fractions on a ruler or tape measure
Download a free printable ruler with fraction measurements marked to help learn how to find the inch fractions for a measurement and for easy reading.

Converting Inches to Metric Measurements

Fraction Decimal and Metric Equivalents

See fraction, decimal, and metric(in millimeters) versions of measurements up to one inch in 164” increments.

Fraction Decimal Millimeters
164 0.015625 0.396875
132 0.03125 0.79375
364 0.046875 1.190625
116 0.0625 1.5875
564 0.078125 1.984375
332 0.09375 2.38125
764 0.109375 2.778125
18 0.125 3.175
964 0.140625 3.571875
532 0.15625 3.96875
1164 0.171875 4.365625
316 0.1875 4.7625
1364 0.203125 5.159375
732 0.21875 5.55625
1564 0.234375 5.953125
14 0.25 6.35
1764 0.265625 6.746875
932 0.28125 7.14375
1964 0.296875 7.540625
516 0.3125 7.9375
2164 0.328125 8.334375
1132 0.34375 8.73125
2364 0.359375 9.128125
38 0.375 9.525
2564 0.390625 9.921875
1332 0.40625 10.31875
2764 0.421875 10.715625
716 0.4375 11.1125
2964 0.453125 11.509375
1532 0.46875 11.90625
3164 0.484375 12.303125
12 0.5 12.7
3364 0.515625 13.096875
1732 0.53125 13.49375
3564 0.546875 13.890625
916 0.5625 14.2875
3764 0.578125 14.684375
1932 0.59375 15.08125
3964 0.609375 15.478125
58 0.625 15.875
4164 0.640625 16.271875
2132 0.65625 16.66875
4364 0.671875 17.065625
1116 0.6875 17.4625
4564 0.703125 17.859375
2332 0.71875 18.25625
4764 0.734375 18.653125
34 0.75 19.05
4964 0.765625 19.446875
2532 0.78125 19.84375
5164 0.796875 20.240625
1316 0.8125 20.6375
5364 0.828125 21.034375
2732 0.84375 21.43125
5564 0.859375 21.828125
78 0.875 22.225
5764 0.890625 22.621875
2932 0.90625 23.01875
5964 0.921875 23.415625
1516 0.9375 23.8125
6164 0.953125 24.209375
3132 0.96875 24.60625
6364 0.984375 25.003125
1″ 1 25.4

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