42 mm to Inches
Convert 42 millimeters to inches — instant, accurate, and easy
The Answer
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How to Convert 42 mm to Inches
To convert 42 millimeters to inches, divide the millimeter value by 25.4. This is because one inch equals exactly 25.4 millimeters — a standard defined by international agreement.
The Calculation
Applying the formula to 42 mm:
Result Summary for 42 mm
- Decimal inches: 1.6535″
- Fractional inches: 1 21/32″ (nearest 1/64)
- Feet and inches: 0 ft 1.65 in
Reference Table — Values Near 42 mm
| Millimeters | Decimal Inches | Fractional Inches |
|---|---|---|
| 39 mm | 1.5354″ | 1 17/32″ |
| 40 mm | 1.5748″ | 1 37/64″ |
| 41 mm | 1.6142″ | 1 39/64″ |
| 42 mm | 1.6535″ | 1 21/32″ |
| 43 mm | 1.6929″ | 1 11/16″ |
| 44 mm | 1.7323″ | 1 47/64″ |
| 45 mm | 1.7717″ | 1 49/64″ |
42 mm in Other Units
Millimeters convert cleanly into every other length unit. Here is 42 mm expressed seven different ways — useful when a drawing, spec sheet or supplier quotes a unit other than inches.
| Unit | 42 mm equals |
|---|---|
| Centimeters (cm) | 4.2 cm |
| Meters (m) | 0.042 m |
| Inches (in) | 1.6535 in |
| Feet (ft) | 0.1378 ft |
| Yards (yd) | 0.04593 yd |
| Thousandths of an inch (mil) | 1,653.5 mil |
| Typographic points (1/72 in) | 119.06 pt |
How Accurate Is Each Fraction of 42 mm?
42 mm equals 1.6535″ (rounded to four decimal places). Any fraction is a further rounding of the full-precision value, so each one carries a small error. This table shows the closest fraction at each common denominator and how far it actually sits from 42 mm.
| Rounded to | Fraction | Decimal | Fraction vs. original |
|---|---|---|---|
| Nearest 1/2″ | 1 1/2″ | 1.5000″ | −3.900 mm (below original) |
| Nearest 1/4″ | 1 3/4″ | 1.7500″ | +2.450 mm (above original) |
| Nearest 1/8″ | 1 5/8″ | 1.6250″ | −0.725 mm (below original) |
| Nearest 1/16″ | 1 5/8″ | 1.6250″ | −0.725 mm (below original) |
| Nearest 1/32″ | 1 21/32″ | 1.6563″ | +0.069 mm (above original) |
| Nearest 1/64″ | 1 21/32″ | 1.6563″ | +0.069 mm (above original) |
For woodworking, DIY and general workshop use, 1 21/32″ is the practical choice — it lands within 0.4 mm of 42 mm. For machining, toolmaking or CAD, use the decimal value 1.6535″ rather than any fraction.
FAQ About 42 mm to Inches
How many inches is 42 mm?
42 millimeters equals 1.6535 inches (rounded to 4 decimal places), or approximately 1 21/32″ (nearest 1/64 inch).
How accurate is the 42 mm to inches conversion?
The conversion of 42 mm to 1.6535 inches uses the exact definition 1 inch = 25.4 millimeters; the four-decimal result is rounded, so it is approximate.
Can I convert 42 mm to feet?
Yes. 42 millimeters equals approximately 0 ft 1.65 in.
📏 Need to measure 42mm accurately?
A steel ruler marked in millimeters makes it easy to find 42 mm (≈ 1.6535″). See current options:
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