Millimeter to Inch

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Result

0.0394

in

Conversion rate: 1 mm = 0.0394 in

Showing up to 4 decimal

How it works

The converter uses exact SI-based factors (e.g., 1 foot = 0.3048 meters, 1 inch = 0.0254 meters).

Formula: inchs = millimeter × 0.0394

Results show between 0 and 8 decimal places and hide trailing zeros for readability.

Conversion Table

Millimeter Inch
0.001 mm 0.00003937 in
0.01 mm 0.0004 in
0.1 mm 0.0039 in
1 mm 0.0394 in
10 mm 0.3937 in
100 mm 3.937 in
1000 mm 39.3701 in

History

Millimeter (mm)

The millimeter, abbreviated mm, stands for one-thousandth of a meter and is crucial for precise measurement tasks. Introduced with the metric system in the late 1700s, the millimeter allows for extremely detailed measurements, which is why it is vital in engineering, machining, and manufacturing. Its precision helps create parts that fit perfectly together. The millimeter is also commonly used in science, including microscopy, material studies, and building construction. Although it measures a tiny length, the millimeter has played a major role in enhancing accuracy and global measurement standards.

Inch (in)

The inch, abbreviated as in, is a length unit in the imperial and US customary systems. Its history reaches back to ancient civilizations, including the Romans, Egyptians, and Anglo-Saxons. Originally, the inch was determined by the width of a human thumb, but it was eventually set as 1/12 of a foot. Since 1959, the inch has been officially defined as exactly 2.54 centimeters due to an international agreement. Inches are still widely used in the United States, Canada, and the UK, especially for construction, manufacturing, and personal measurements. Even with the global shift to metric units, the inch remains important in certain fields such as technical drawings, screen dimensions, and household tools.

Other Relevant Conversions

m → cm m → mm m → km m → in m → ft m → yd m → mi m → µm m → nm cm → m cm → mm cm → km cm → in cm → ft cm → yd cm → mi cm → µm cm → nm mm → m mm → cm mm → km mm → in mm → ft mm → yd mm → mi mm → µm mm → nm km → m km → cm km → mm km → in km → ft km → yd km → mi km → µm km → nm in → m in → cm in → mm in → km in → ft in → yd in → mi in → µm in → nm ft → m ft → cm ft → mm ft → km ft → in ft → yd ft → mi ft → µm ft → nm yd → m yd → cm yd → mm yd → km yd → in yd → ft yd → mi yd → µm yd → nm mi → m mi → cm mi → mm mi → km mi → in mi → ft mi → yd mi → µm mi → nm µm → m µm → cm µm → mm µm → km µm → in µm → ft µm → yd µm → mi µm → nm nm → m nm → cm nm → mm nm → km nm → in nm → ft nm → yd nm → mi nm → µm