November 15, 2023
How to Convert from MM to Mils: a Guide for Beginners
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Before we discuss how to convert MM to mils, it's essential to mention the metric system and the imperial system.
Our focus is on mm, a metric unit, and its conversion to mils, an imperial unit.
However, mils are sometimes used in a different context as milliradians (mils), which are units of angular measurement commonly used in ballistic calculations and optical instruments.
To convert from millimeters to mils, you can use the following straightforward conversion formula:
Mils = Millimeters * 39.37
We can derive this formula the following way:
Let's illustrate this with an example: Suppose you have a measurement of 0.5 mm and want to convert it to mils:
Mils = 0.5 mm * 39.37 ≈ 19.685 mils
So, 50 millimeters is approximately 19.685 mils. That's about the thickness of two business cards!
This conversion is essentially the reverse of our previous equation. You can use the following straightforward conversion formula:
Let's walk through an example of converting from mils to millimeters using the conversion formula:
Suppose you have a measurement of 50 mils, and you want to convert it to millimeters. You can use the formula as follows:
Millimeters (mm) = 50 mils / 39.37 ≈ 1.27 mm
So, 50 mils are approximately equivalent to 1.27 millimeters. That's about the thickness of a U.S. Dime!
1 mil = 0.0254 Millimeter
For those who prefer visual aids, having a conversion chart on hand is common. Here's a short conversion chart we made to give you an idea:
In this chart, we have provided conversions for mils ranging from 1 to 120. This should cover most conversion needs. However, if you require conversions for values outside this range, simply use the conversion formulas mentioned earlier.
Mils are frequently employed in precision applications in the US, where small measurements are crucial. Below are specific scenarios where mils come into play for electrical engineers:
For SMT components in PCB design, there are part size references that are commonly used and are crucial for specifying dimensions on the PCB. This table provides their size values in both mils and millimeters for easy reference during PCB design and assembly:
We've mentioned milliradians earlier, so let's clarify what they are. A milliradian, often denoted as "mrad" or "mil," is a unit of angular measurement. It is used in various fields, including ballistics and engineering. When you hear talk about a mil-dot scope or mil reticle, it's referring to measurements in milliradians. In this context, one radian is divided into 1,000 milliradians, and the reticle markings are spaced at one milliradian intervals.
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