Inch Fraction Calculator
Add, subtract, multiply, or divide fractional inch measurements. Results shown as a simplified mixed number, decimal inches, millimeters, and centimeters.
Fraction Arithmetic
Quick Examples
First Value (A)
Whole
+Fraction
"Operation
Second Value (B)
Whole
+Fraction
"✏️
Enter values above to see the result
How Fraction Arithmetic Works
Addition & Subtraction
Find the least common denominator (LCD), convert both fractions, then add or subtract numerators. Reduce to lowest terms.
1/4 + 3/8 = 2/8 + 3/8 = 5/8Multiplication
Multiply numerators together and denominators together, then simplify. Mixed numbers are converted to improper fractions first.
1/2 × 2/3 = 2/6 = 1/3Division
Multiply by the reciprocal of the divisor (flip the second fraction), then simplify.
3/4 ÷ 1/2 = 3/4 × 2/1 = 6/4 = 3/2 = 1 1/2Mixed Numbers
Whole parts are converted to improper fractions before any calculation: e.g. 1 3/4 = 7/4. Result is then converted back to mixed number form.
1 1/2 + 2 1/4 = 3/2 + 9/4 = 6/4 + 9/4 = 15/4 = 3 3/4Common Addition Reference
| A | + | B | Sum |
|---|---|---|---|
| 1/4" | + | 1/4" | 1/2" |
| 1/4" | + | 1/2" | 3/4" |
| 1/8" | + | 1/8" | 1/4" |
| 3/8" | + | 1/8" | 1/2" |
| 3/8" | + | 5/8" | 1" |
| 1/2" | + | 1/4" | 3/4" |
| 3/4" | + | 1/4" | 1" |
| 1/16" | + | 1/16" | 1/8" |
How to Use
- 1Enter the first inch measurement — whole number and/or fraction.
- 2Select your operation: +, −, ×, or ÷.
- 3Enter the second measurement.
- 4Result appears instantly as a simplified fraction, decimal, mm, and cm.
Fraction Reference
1/16"0.0625"
1/8"0.125"
3/16"0.1875"
1/4"0.25"
5/16"0.3125"
3/8"0.375"
7/16"0.4375"
1/2"0.5"
3/4"0.75"
1"1.0"