How many mm in 1 em?
The answer is 4.2175176.
We assume you are converting between millimetre and em.
You can view more details on each measurement unit: mm or
em
The SI base unit for length is the metre.
1 metre is equal to 1000 mm, or 237.10630158366 em.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between millimetres and em.
Type in your own numbers in the form to convert the units!

››Quick conversion chart of mm to em

1 mm to em = 0.23711 em

5 mm to em = 1.18553 em

10 mm to em = 2.37106 em

20 mm to em = 4.74213 em

30 mm to em = 7.11319 em

40 mm to em = 9.48425 em

50 mm to em = 11.85532 em

75 mm to em = 17.78297 em

100 mm to em = 23.71063 em

››Want other units?

You can do the reverse unit conversion from
em to mm, or enter any two units below:

A millimetre (American spelling: millimeter, symbol mm) is one thousandth of a metre, which is the International System of Units (SI) base unit of length. The millimetre is part of a metric system. A corresponding unit of area is the square millimetre and a corresponding unit of volume is the cubic millimetre.

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