Calculate inches from feet by multiplying by 12, convert inches back to feet, or combine feet and inches into a total length with fraction or decimal rounding.
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Feet to Inches Formula
This calculator works in three directions. Use the formula that matches what you are solving for.
To convert feet to inches:
in = ft * 12
To convert inches to feet:
ft = in / 12
To combine a feet value and an inches value into one total length:
total in = (ft * 12) + in
- in = length in inches
- ft = length in feet
- 12 = the number of inches in one foot
One foot is defined as exactly 12 inches, so the conversion factor never changes. When you convert feet to inches you multiply by 12, and when you convert inches to feet you divide by 12. The combine mode adds the inches that come from the feet value to any extra inches you enter, which is useful when a measurement is written as a mix of both units, such as 5 feet 6 inches. The advanced options let you round the inch result to the nearest common fraction (down to 1/16 inch) or choose how many decimal places to display.
Feet and Inches Conversion Reference
The table below shows common whole-foot values converted to inches. Multiply any feet value by 12 to extend it.
| Feet | Inches |
|---|---|
| 1 ft | 12 in |
| 2 ft | 24 in |
| 3 ft | 36 in |
| 5 ft | 60 in |
| 5.5 ft | 66 in |
| 6 ft | 72 in |
| 10 ft | 120 in |
| 100 ft | 1,200 in |
The next table converts common fractions of a foot into inches, which helps when a measurement is written as a decimal.
| Decimal Feet | Inches |
|---|---|
| 0.25 ft | 3 in |
| 0.5 ft | 6 in |
| 0.75 ft | 9 in |
| 0.1 ft | 1.2 in |
Example Problems
Example 1. You have a length of 7 feet and want it in inches. Multiply the feet by 12.
in = 7 * 12 = 84 inches
Example 2. A board is measured as 5 feet 6 inches and you need the total length in inches. Convert the feet first, then add the extra inches.
total in = (5 * 12) + 6 = 60 + 6 = 66 inches
FAQ
How many inches are in a foot?
There are exactly 12 inches in one foot. This is a fixed definition, so the conversion is always the same regardless of the size of the measurement.
How do you convert feet to inches?
Multiply the number of feet by 12. For example, 4 feet equals 4 times 12, which is 48 inches. If your feet value has a decimal, multiply the whole value by 12, so 4.5 feet equals 54 inches.
How do you handle a measurement written as feet and inches?
Convert the feet portion to inches by multiplying by 12, then add the leftover inches. A measurement of 3 feet 4 inches becomes (3 times 12) plus 4, which equals 40 inches. The combine mode on this calculator does this for you.
