Working with fractions is a fact of life in the shop. Now, I don’t mind doing math, but adding and subtracting fractions can make my head spin and lead to errors. What’s worse, trying to use a calculator that only understands decimals is a hassle. Fortunately, there are calculators to help you guarantee your math and measurements are dead-on accurate.

**Working in Inches**

Some calculators let you input whole and fractional inch dimensions. And the results are displayed in feet and inches, too. For example, when I need to add the length of two 3/8"-long stub tenons to a frame rail that’s 12-13/16" long, these calculators make it an easy, intuitive task.

**Common Fractions**

The Inch-Mate+ calculator by Sonin uses a different approach for entering fractions. It has four specific keys for entering fractional inches based on the denominator. This feature does save a few to sixteenths. And the answers are rounded to the nearest 1/16" or converted to decimal feet, not inches like you’d expect.

**Features of a Shop Calculator **

At first glance, you might be overwhelmed by it all. Entering something like 81-15/16" in inches can be a little confusing with some shop calculators. But it only takes a little time to learn how to estimate lumber dimensions. The way you enter feet, inches, and make fractions is actually more intuitive than you might think. Once you’ve entered the numbers, doing math in the shop a breeze. After entering a value, you can perform any calculation on it you need. You can even have the results displayed to the nearest 1/64" if you wish. Add one to your shop and you’ll appreciate the extra help available at your fingertips.

**Easy to Use**

Calculated Industries has a variety of models that are handy for all sorts of shop and home tasks. Their Measure Master Pro is one example. But I find their basic Home ProjectCalc even nicer. Their calculators include “Feet,” “Inch,” and other special keys for entering fractions. This can come in very handy when building outdoor projects, like a backyard playhouse or gazebo. Once you get the hang of it, entering any shop measurement becomes second nature. After using one of these calculators in the shop, I couldn’t do without it. You can keep one in your apron pocket.

**Metric Wood Calculators**

If you work in metric units, you can find calculators that understand meters or millimeters and convert them to feet and inches. If your shop math involves metric units, Calculated Industries and FastCap offer a solution. These calculators handily convert your fractional inches to metric units (millimeters or meters) and vice-versa. The ProjectCalc Plus MX (model 8528) by Calculated Industries follows in the long line of project-based calculators. Like their other calculators, it includes features for calculating materials and areas for a number of typical home projects.

The Convertor Pro by FastCap doesn’t have all the bells and whistles, but it’s easy to use. You can’t enter feet dimensions, but it works great for fractional inches and millimeter calculations. Yard, feet, and inch keys are used for entering or converting dimensions. Powerful Convert key converts between metric and imperial dimensions and accesses secondary functions on other keys. Hinged cover closes to keep out dust and prevent scratches. Display can show feet, inches, fractions, decimal inches, or metric measurements. Fraction bar makes entering any type of fraction an easy task.