📏 Inches to Fraction Calculator
Translate decimal inch measurements into easy-to-read fractions, complete with metric equivalents.
Select your preferred denominator precision (up to 1⁄64). The calculator rounds to the nearest fraction and simplifies the result.
Enter a non-negative decimal measurement.
Choose how precise the fraction should be.
Nearest Fraction
2 6/16
Reduced Fraction
2 3/8
Millimeters (mm)
60.32
How to Use This Calculator
Enter the decimal inch measurement
Type the decimal value from your caliper, tape measure, or digital readout.
Choose the denominator
Select the maximum denominator (1/8 through 1/64). The calculator rounds to the nearest available fraction.
Read the fractional result
View both the raw and simplified fraction, plus a millimeter equivalent for cross-system communication.
Formula
Fraction = round(decimal × denominator) ÷ denominator
Reduced Fraction = Fraction ÷ gcd(numerator, denominator)
The calculator uses the greatest common divisor (GCD) to simplify the fraction automatically.
Use the formula breakdown to confirm the calculation logic or perform the conversion manually if needed.
Full Description
Craftspeople, machinists, and DIYers often need to record or communicate measurements in fractional inches. This calculator bridges decimal outputs from digital tools with the fractional notation common on shop plans.
By allowing you to set the maximum denominator, the tool ensures compatibility with rulers and gauges that only display certain increments. Simplified fractions help avoid confusion when reading cut lists or assembly guides.
The millimeter equivalent supports teams working across imperial and metric systems, reducing conversion errors when sourcing parts or materials internationally.
Frequently Asked Questions
What if the fraction rounds to 1?
When the fractional part rounds up to a whole inch, the calculator increments the whole number and sets the fraction to 0.
Can I choose a denominator larger than 64?
Not currently. If you need finer precision, you can extend the options in the source or work directly with decimal inches.
Why are there two fraction outputs?
The first shows the rounded fraction before simplification (useful for matching the chosen denominator). The second displays the reduced form for cleaner communication.
How accurate is the millimeter conversion?
It uses the exact factor 1 in = 25.4 mm. Results are rounded to two decimal places for readability.