This is the inches to fractions calculator, a simple and intuitive tool that helps you convert any decimal to fraction inches. Do you want to transform the length measured in mm to inches fraction? That's not a problem at all! Alternatively, you can also turn any fraction to inches, and then to its inch fraction, adjusting for the appropriate precision. Converting inches to fractions has never been this entertaining, has it?

How to convert decimal to fraction inches?

Transforming a distance in its decimal form to its fraction inches is almost the same as converting any decimal to a regular fraction. Almost. Principally, we have to find the ratio of two numbers, the numerator and the denominator. The only difference is that the denominator should be to the power of 2: 2, 4, 8, 16, etc.

So, how to convert decimal to inch fraction?

  • Let's take your decimal value, x
  • Choose the precision, or in other words, the value of denominator, d
  • Multiply these numbers and round them to the closest whole number, n = round(d*x)
  • The resulting inch fraction is then n/d

As you can see, the outcome is sometimes only an approximation of real value because of rounding. But for typical everyday measurements, it's accurate enough, especially when you choose a precision of 1/32 or higher.

By the way, did you know that music intervals also rely on dyadic fractions (fractions with the denominator 2ⁿ), as it concerns frequencies?

How to convert distance in mm to inches fraction?

Imagine you want to buy new tires for your bike, or you're preparing a spot for your new TV. You take out your ruler or meterstick, and get to measuring. But it's in mm, or cm, or another metric unit your not exactly familiar with. So, is there an easy way to convert mm to inches fraction?

The answer is YES:

  1. If you have the length in mm, divide the result by 25.4

  2. If you have the length in cm, divide the result by 2.54

  3. If you have the length in m, divide the result by 0.0254

  4. Then convert this decimal to fraction inches as you've learned from the previous section

You can convert any length unit to inches, but you don't have to remember all the formulas by heart - just use our inches to fraction calculator, and choose one of the most common length units.

Fraction to inches conversion table

Take a look at this table if you want to find any inch fraction between 0" and 1", with steps of 1⁄64".

Fraction Inches
Decimal Inches ["]
Millimeters [mm]
1⁄64"
0.015625
0.396875
1⁄32"
0.03125
0.79375
3⁄64"
0.046875
1.190625
1⁄16"
0.0625
1.5875
5⁄64"
0.078125
1.984375
3⁄32"
0.09375
2.38125
7⁄64"
0.109375
2.778125
1⁄8"
0.125
3.175
9⁄64"
0.140625
3.571875
5⁄32"
0.15625
3.96875
11⁄64"
0.171875
4.365625
3⁄16"
0.1875
4.7625
13⁄64"
0.203125
5.159375
7⁄32"
0.21875
5.55625
15⁄64"
0.234375
5.953125
1⁄4"
0.25
6.35
17⁄64"
0.265625
6.746875
9⁄32"
0.28125
7.14375
19⁄64"
0.296875
7.540625
5⁄16"
0.3125
7.9375
21⁄64"
0.328125
8.334375
11⁄32"
0.34375
8.73125
23⁄64"
0.359375
9.128125
3⁄8"
0.375
9.525
25⁄64"
0.390625
9.921875
13⁄32"
0.40625
10.31875
27⁄64"
0.421875
10.715625
7⁄16"
0.4375
11.1125
29⁄64"
0.453125
11.509375
15⁄32"
0.46875
11.90625
31⁄64"
0.484375
12.303125
1⁄2"
0.5
12.7
33⁄64"
0.515625
13.096875
17⁄32"
0.53125
13.49375
35⁄64"
0.546875
13.890625
9⁄16"
0.5625
14.2875
37⁄64"
0.578125
14.684375
19⁄32"
0.59375
15.08125
39⁄64"
0.609375
15.478125
5⁄8"
0.625
15.875
41⁄64"
0.640625
16.271875
21⁄32"
0.65625
16.66875
43⁄64"
0.671875
17.065625
11⁄16"
0.6875
17.4625
45⁄64"
0.703125
17.859375
23⁄32"
0.71875
18.25625
47⁄64"
0.734375
18.653125
3⁄4"
0.75
19.05
49⁄64"
0.765625
19.446875
25⁄32"
0.78125
19.84375
51⁄64"
0.796875
20.240625
13⁄16"
0.8125
20.6375
53⁄64"
0.828125
21.034375
27⁄32"
0.84375
21.43125
55⁄64"
0.859375
21.828125
7⁄8"
0.875
22.225
57⁄64"
0.890625
22.621875
29⁄32"
0.90625
23.01875
59⁄64"
0.921875
23.415625
15⁄16"
0.9375
23.8125
61⁄64"
0.953125
24.209375
31⁄32"
0.96875
24.60625
63⁄64"
0.984375
25.003125
1"
1
25.4

Let's convert inches to fraction - inches to fraction calculator in practice

Imagine you've bought a wooden panel, 5 meters long. You plan to cut it into six equal parts, but you have only a tape measure with the fractional inches scale. We can measure the length with precision down to 1/32". Here is how to deal with the problem:

  1. Divide 5 m by 6, 5 m / 6 = 5/6 m. It's the length of each part.

  2. Convert the measurement in mm to inches by dividing the value by 25.4, and rounding the outcome to two decimal digits (those will be our significant figures): (5/6 m) / 25.4 = 32.81 in.

  3. Our precision is 1/32". Multiply the value above by 32: 32.81 in * 32 = 1049.92 in.

  4. Round the outcome to the nearest whole number, 1050 in.

  5. Finally, we can convert the length from inches to fraction: 1050/32".

  6. As there are countless equivalent fractions to our result, we can make our lives easier by simplifying this inch fraction. Find the least common multiple of 1050 and 32, which is 2. Divide both numerator and denominator by 2, so we get 525/16". As it's an improper fraction, convert it to a mixed number: 32 13/16" (you can use the modulo operation to find the quotient quickly). If you want to go even further, let's extract feet from the result of the mm to inches fraction conversion. The result is finally: 2' 8 13/16"

As you can see, there are a few steps you should take to obtain the outcome. You can save time by using our inches to fractions calculator, as it shows the result immediately!

Wojciech Sas, PhD candidate