In Metric vs. Imperial resource guide, I will not be discussing which system of measurement is “better”. What I really want to talk about is what makes them different as well as what the advantages and disadvantages of each system of measurement are.
Like almost all of us in the United States, I grew up learning and have become accustomed to the measurements of feet and inches. However, the good news is converting to metric isn’t as difficult as one may think. The metric system is a universal measuring system; the only places that do not use the metric system are the United States, Liberia, and Myanmar. Again, it’s important to keep in mind that one isn’t necessarily “better” than the other. Both imperial and metric can get the job done. They both can lead to the same end result; they just do it in different ways.
Pros and Cons of Metric and Imperial Measurements
When using 3D design software to create projects in most cases using metric measurements is easier. People find, including me, that in these cases it’s faster and fewer errors are made. Let’s do a quick example, what’s half of 238mm? Well, half of 200 is 100 and half of 38 is 19. So 119 millimeters. That’s pretty straightforward, right?
On the other hand, let’s say I was using inches and I found I needed to cut a 12 ⅓” board in half. Can you cut that number in half fairly quickly, I can’t. In case you’re curious it’s 6 and ⅙ “.
Metric Doesn’t Have a Middle Man
Now, you may be wondering “What on earth do you mean that the metric system doesn’t have a middle man”? Let me explain. There is a pretty big difference between the metric system and imperial system because of this. The imperial system has a “middle man” or better yet a middle unit which is the foot.
This unit is very useful for breaking down large measurements into something more understandable. It’s easy for people who use the imperial system to wrap their heads around someone telling them that their trailer is 17’ 5” feet long. Imagine if someone said to you, “Oh yeah, my trailer is 209” long”. I don’t know about you but that’s not something I can really picture in my head.
The metric system starts with a tiny unit that is very popular, the millimeter. Next in line is the centimeter. I think it’s safe to say that both of those measurements can be considered pretty small. But you may be wondering, what happens after that? The metric system then jumps all the way to the meter which is 100 cm. There technically is no “middle man”. Let me clarify, there is a middle measurement but it’s not used in the metric system. It’s called the decimeter.
Metric Isn’t Always the Simplest Option
As stated previously, the metric system is a universal measurement that is logical, intuitive, and easier to design with. It also is more superior than imperial when it comes to adding numbers, subtracting numbers, multiplying numbers, as well as dividing numbers. I feel like I should mention that it’s a common practice for a lot of people to use both systems of measurement while they work. However, there are also a lot of people that say they prefer imperial because it just has a slightly better edge.
Either way you should decide what works best for you. Will you benefit from switching from Imperial to Metric or from Metric to Imperial, or even learning both? We can’t answer that for you. The good news is we made converting from one to the other easy with conversion charts that you can find below. These are a great resource to use if you’re first starting out and then once you get more comfortable there are plenty of conversions you should be able to make on your own.
Conversion Charts
| US (Inches) | Decimal Inches | Metric (millimeters) |
| 1/16 | 0.0625 | 1.6 |
| 1/8 | 0.125 | 3.2 |
| 3/16 | 0.1875 | 4.8 |
| 1/4 | 0.250 | 6.4 |
| 5/16 | 0.3125 | 7.9 |
| 3/8 | 0.375 | 9.5 |
| 7/16 | 0.4375 | 11 |
| 1/2 | 0.500 | 13 |
| 9/16 | 0.5625 | 14 |
| 5/8 | 0.625 | 16 |
| 11/16 | 0.6875 | 17 |
| 3/4 | 0.750 | 19 |
| 13/16 | 0.8125 | 21 |
| 7/8 | 0.875 | 22 |
| 15/16 | 0.9375 | 24 |
| 1 | 1.000 | 25 |
| 1 – 1/8 | 1.125 | 29 |
| 1 – 1/4 | 1.250 | 32 |
| 1 – 3/8 | 1.375 | 35 |
| US (Inches) | Decimal Inches | Metric (millimeters) |
| 1 – 1/2 | 1.500 | 38 |
| 1 – 5/8 | 1.625 | 41 |
| 1 – 3/4 | 1.750 | 45 |
| 1 – 7/8 | 1.875 | 48 |
| 2 | 2.000 | 51 |
| 2 – 1/4 | 2.250 | 57 |
| 2 – 1/2 | 2.500 | 64 |
| 2 – 3/4 | 2.750 | 70 |
| 3 | 3.000 | 76 |
| 3 – 1/4 | 3.250 | 83 |
| 3 – 1/2 | 3.500 | 89 |
| 3 – 3/4 | 3.750 | 95 |
| 4 | 4.000 | 102 |
| 4 – 1/2 | 4.500 | 114 |
| 5 | 5.000 | 127 |
| 5 – 1/2 | 5.500 | 140 |
| 6 | 6.000 | 152 |
| 6 – 1/2 | 6.500 | 165 |
| 7 | 7.000 | 178 |
There is Metric vs. Imperial, there can be quite a lot of confusion between the metric and imperial systems, including how to change measurements from one to the other. We hope this resource helped you get a better understanding of these measuring systems overall. Please come back to this guide as many times as you need to reference back to the charts. If you have any other questions please feel free to leave a comment, we would love to hear from you!
Check out our other resource guides Bite-Size Guide: Best Drill Bit Size Chart, US Screw Sizes, and How to Use a Drill and Tap Chart.
