40 millimeters in inches

Conversion formula
How to convert 40 millimeters to inches?

We know (by definition) that: $1\mathrm{mm}\approx 0.039370079\mathrm{in}$

We can set up a proportion to solve for the number of inches.

Now, we cross multiply to solve for our unknown $x$:

Conclusion: 40 ⁢ mm ≈ 1.57480316 ⁢ in

Conversion in the opposite direction

The inverse of the conversion factor is that 1 inch is equal to 0.635 times 40 millimeters.

It can also be expressed as: 40 millimeters is equal to $\frac{1}{\mathrm{0.635}}$ inches.

Approximation

An approximate numerical result would be: forty millimeters is about one point five seven inches, or alternatively, a inch is about zero point six four times forty millimeters.