42.243 Millimeters to Inches

42.243 mm ≈ 1.6631 in

Closest fraction: 1 2132(1.65625 in — differs by less than 1%)

Calculation: in = 42.243 mm × 0.0393701 ≈ 1.6631 in

Millimeter to Inch Converter

Choose the type of measurement to convert
Select the source unit to convert from
Select the target unit to convert to
Enter a numeric value or fraction to convert
Sig. Figures:

How long is 42.243 mm?

42.243 mm (4.22 cm) is comparable to the width of a thumb or the diameter of a coin.

What does 42.243 mm look like?

Comparable to the width of a thumb or the diameter of a coin
42.243 mm (4.22 cm) is comparable to the width of a thumb or the diameter of a coin.

42.243 mm on the inch scale

mm01020304050in00.511.5

42.24 mm = 1.663 in

How to Convert Millimeter to Inch

1 millimeter = 0.0393701 inches exact

Inch = Millimeter × 0.0393701

Example: 42.243 mm × 0.0393701 = 1.6631 in

Reverse Conversion

To convert inches back to millimeters:

  • Remember, 1 inch equals 25.4 millimeters.
  • To convert 1.6631 in to mm, multiply 1.6631 x 25.4, resulting in 42.243 mm.

exact This conversion factor is exact by international definition.

42.243 mm is also equal to:

  • 4.2243 centimeter
  • 0.042243 meter
  • 0.13859 feet
  • 0.046198 yard
About these units

Millimeter: Metric unit equal to one thousandth (1/1000) of a meter.

Inch: Imperial/US customary unit standardized as exactly 25.4 millimeters since 1959.

Frequently Asked Questions

How much is 42.243 millimeters in inches?

42.243 millimeters equals 1.6631 inches. This is calculated by multiplying 42.243 by the conversion factor 0.0393701.

What does 42.243 millimeters look like in inches?

42.243 millimeters (1.6631 inches) is one to four inches — a small component or connector.

How do you calculate 42.243 millimeters to inches?

Multiply 42.243 by the conversion factor 0.0393701. The calculation is 42.243 × 0.0393701 = 1.6631 inches. This factor is defined by international measurement standards.

Share This Calculation

42.243 millimeters = 1.66311 inches
42.243 millimeters = 1.66311 inches — conversion chart

For general conversions between millimeters and inches, see the millimeters to inches converter.

Conversion factors verified against NIST, BIPM, ISO 80000-3 1 inch = 2.54 cm by international agreement (1959). Last reviewed: March 2026
Tiago Fernandes Reviewed by Tiago Fernandes

All unit conversions on CoolConversion use conversion factors defined or documented by internationally recognised standards bodies (such as ISO and NIST), including both SI and non-SI units.