Millimeters to inches (mm to in) converter

tape measure for mm and inches - icon

Use this tool to convert quickly between millimeters/millimetres and inches (mm and in), or vice-versa, with results given as both decimal and fraction. If you're converting mm to inches, you can choose to have a fraction result in 1/16, 1/32 and 1/64 inch if you wish.

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Whilst every effort has been made in building this millimeters and inches conversion tool, we are not to be held liable for any special, incidental, indirect or consequential damages or monetary losses of any kind arising out of or in connection with the use of the converter tools and information derived from the web site. This millimeters and inches conversion tool is here purely as a service to you, please use it at your own risk. Do not use calculations for anything where loss of life, money, property, etc could result from inaccurate conversions.

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How many inches in a mm?

1mm = 0.03937008 inches. To convert mm to inches you need to divide your figure by 25.4.

How many mm in an inch?

1 inch = 25.4mm. To convert inches to millimeters multiply your figure by 25.4. The chart below shows some example conversions, rounded to a maximum of 4 decimal places. Should you wish to convert between centimeters and inches, give the cm to inches converter a try.

How many mm in an inch and a half?

1 1/2 inches = 38.1 mm. To get this answer, we simply multiply: 25.4 × 1.5.

mm to inches as fraction

The converter on this page allows you to show results as fractions in 1/16, 1/32 and 1/64 inch for millimeter to inch conversions. It is important to note that when you choose this option, the converter will round (up or down) and give you a remainder figure (the difference between the fraction and the full result). For this reason, the fraction result will be slightly smaller or slightly larger.

mm to inches conversion chart

Note: fraction figures for inches are approximate.

Millimeters Inches (decimal) Inches (fraction approx)
1mm 0.0394 in 1/32 inch
10mm 0.3937 in 25/64
20mm 0.7874 in 25/32
30mm 1.1811 in 1 3/16
40mm 1.5748 in 1 37/64
50mm 1.9685 in 1 31/32
60mm 2.3622 in 2 23/64
70mm 2.7559 in 2 3/4
80mm 3.1496 in 3 5/32
90mm 3.5433 in 3 35/64
100mm 3.937 in 3 15/16

My conversion tool can help you convert between millimeters and inches. Should you wish to convert centimeters to inches, see the cm and inches converter. For other units of height, you may wish to use the height calculator here.

If you have any suggestions or queries about this conversion tool, please contact me.

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