Overview: Calc-Tools Online Calculator offers a specialized Feet-Inch-Sixteenth (FIS) converter tool designed to simplify complex calculations involving feet and inches. This free tool eliminates the hassle of manual operations like addition, subtraction, multiplication, and division within the imperial system, and seamlessly handles conversions between decimals and fractions. Users can input values in various formats—including decimals, fractions, integers with fractions, and basic arithmetic expressions—for maximum flexibility. The calculator provides precise results tailored to the chosen operation, outputting results in feet, inches, and fractional inches, or in square units for multiplication. It’s an essential resource for anyone needing quick, accurate, and effortless imperial measurement calculations.

Master Measurements with Our Free Online Calculator

Navigating calculations involving feet and inches can be a common source of frustration. The challenges of adding, subtracting, multiplying, and dividing these units, not to mention converting between decimals and fractions, are well-known. Fortunately, a specialized solution exists. Our advanced Foot-Inch-Sixteenth (FIS) calculator is designed to eliminate these hassles, providing accurate results instantly.

This guide will explore the powerful features of this essential online calculator and demonstrate how to utilize it effectively. We will also cover fundamental operations, including adding and subtracting measurements that include fractions.

Your Comprehensive Guide to Using the Foot and Inch Calculator

Whether you're tackling a subtraction problem with feet and inches or adding complex fractional inches, this tool provides a straightforward solution. The FIS calculator is engineered to handle all these scenarios with ease.

The process is intuitive: simply input your values in any convenient format. Our free calculator accepts:

  • Standard decimals (like 2.5)
  • Fractions and divisions (such as 1/4 or 1/32)
  • Whole numbers combined with fractions (e.g., 1 + 3/8)
  • Multiplication expressions (e.g., 3 * 4)
  • Subtraction expressions (e.g., 4 - 1)
  • Addition expressions (e.g., 5 + 8)

If a value does not include feet or inches, simply enter '0' in the corresponding field. Your output will vary based on the operation you select from the four available modes:

  • ➕ Add Feet and Inches: The result will display the total in feet, inches, and fractional inches at your chosen precision level.
  • ➖ Subtract Feet and Inches: The result will display the difference in feet, inches, and fractional inches at your chosen precision level.
  • ✖️ Multiply Feet and Inches: The result will be presented in both square feet (ft²) and square inches (in²).
  • ➗ Divide Feet and Inches: The result will be presented as a quotient.

Manual Calculation Example: Area

While the FIS calculator offers the simplest method, understanding the manual process is valuable. Let's calculate the area of a dog kennel as an example.

First, decide if your result should be in square feet (ft²) or square inches (in²). For this example, we'll use square inches.

Next, convert all feet and inches measurements solely into inches. Our integrated length converter can assist with this step. Suppose the kennel walls are 2 feet 6 inches long and 1 foot 5 inches wide.


2 ft 6 in = (2 * 12) + 6 = 30 inches
1 ft 5 in = (1 * 12) + 5 = 17 inches

Then, multiply the converted values:

17 in × 30 in = 510 in²

And there you have the calculated area!

A Step-by-Step Process for Adding Feet and Inches

The "add feet and inches" function is among the most frequently used features. Here is how the calculation works.

Begin with a simple example: adding 2 ft 3 in and 5 ft 6 in. Perform the addition separately for feet and inches.

  • Add the feet: 2 + 5 = 7 ft
  • Add the inches: 3 + 6 = 9 in

Combine the results for a total of 7 ft 9 in. Always ensure the final inch value is less than 12, as 12 inches constitute one full foot.

Adding Feet and Inches with Fractions

The process remains logical when fractions are involved. Consider adding 2 ft 10 1/4 in and 1 ft 2 9/16 in.

First, add the whole feet and whole inches separately.

  • Feet: 2 + 1 = 3 ft
  • Inches: 10 + 2 = 12 in

Since 12 inches equals 1 foot, we add this to the feet total, giving us 4 feet.

Next, add the fractions: 1/4 and 9/16. Find a common denominator, which is the Least Common Multiple (LCM) of 4 and 16, which is 16.


Convert 1/4 to sixteenths: (1/4) = 4/16.
Now add: 4/16 + 9/16 = 13/16 inch.

The final compiled result is 4 ft and 13/16 in.

Frequently Asked Questions (FAQs)

How should I abbreviate feet and inches?

Feet can be abbreviated as "ft" (e.g., 4 ft) or represented with a single apostrophe (4′). Inches can be abbreviated as "in" (e.g., 10 in) or represented with a double apostrophe (10″).

How many feet are in 12 inches?

There are exactly 1 foot in 12 inches. To convert any number of inches to feet, divide the total inches by 12. For example, 30 inches divided by 12 equals 2 feet with a remainder of 6 inches, or 2.5 feet.

30 in / 12 = 2.5 ft

How do I convert 62 inches into feet and inches?

62 inches equals 5 feet and 2 inches (5 ft 2 in). To convert, divide 62 by 12, which gives a quotient of 5 (feet) and a remainder of 2 (inches).

62 ÷ 12 = 5 R2 → 5 ft 2 in

How can I multiply feet and inches?

For example, to multiply 4 ft 3/8 in by 2 ft:

  1. Convert 4 feet to inches: 4 × 12 = 48 inches.
  2. Add the fractional inch: 3/8 inch = 0.375 inch. So, 48 + 0.375 = 48.375 inches.
  3. Convert 2 feet to inches: 2 × 12 = 24 inches.
  4. Multiply: 48.375 in × 24 in = 1161 square inches (in²).