mm to Fraction Calculator
Convert millimeters to fractional inches instantly. Perfect for woodworking, construction, engineering, and DIY projects. Get decimal inches, simplified fractions, and visual results.
Step 1: Enter Millimeters
mm
1/denom
Conversion formula
1 inch = 25.4 mm. Decimal inches = mm / 25.4. Fraction is rounded to the chosen denominator.
Step 2: Fraction Format
Fraction tips
Common denominators: 16 (1/16″), 32 (1/32″), 64 (1/64″). Simplify reduces fractions like 4/16 → 1/4.
Conversion Result
Summary
Fraction Breakdown
Common Conversions
Fractional inches
1″
= 1.0000 in
Millimeters
25.40 mm
Decimal inches
1.0000 in
Fraction (simplified)
1″
Denominator used
16
Fraction Comparison (different denominators)
| Denominator | Fraction | Decimal (in) | Error (in) |
|---|
Exact decimal
1.0000
Rounded fraction
1″
Rounding error
0.0000
mm per inch
25.4
Common mm to inch conversions
Quick reference
| mm | Inches (approx) | Fraction (1/16″) |
|---|---|---|
| 1 mm | 0.0394″ | 1/32″ |
| 5 mm | 0.1969″ | 3/16″ |
| 10 mm | 0.3937″ | 25/64″ |
| 20 mm | 0.7874″ | 25/32″ |
| 25.4 mm | 1.0000″ | 1″ |
Precision matters in your projects
Get professional drafting tools, engineering rulers, and conversion charts. Perfect for workshops and studios.
Request tool guide