Feet and Inches Calculator

Adding, subtracting, multiplying, or dividing measurements in feet and inches is tricky because the math doesn't work in base-10 — the Feet and Inches Calculator handles the unit conversion for you. Enter your first measurement (feet and inches), choose an operation, then enter your second measurement to get the result in feet and inches. You can also set the rounding precision (from nearest inch down to 1/32") and see secondary outputs for total inches and decimal feet.

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Frequently Asked Questions

What are the symbols for feet and inches?

The standard symbols are a single prime (′) for feet and double prime (″) for inches. In everyday writing, you can use a single quote (') for feet and double quote (") for inches.

Is 12 inches the same as 1 foot?

Yes, exactly. There are 12 inches in 1 foot. This is a fixed conversion in the imperial measurement system.

How do you calculate inches from feet manually?

To convert feet to inches, multiply the number of feet by 12. For example, 3 feet = 3 × 12 = 36 inches.

How do you add feet and inches together?

Add the feet separately from the inches. If the inches total 12 or more, convert every 12 inches to 1 foot and add to the feet total.

Can I use fractions in feet and inches calculations?

Yes, you can use fractions, decimals, or mixed numbers for inches. For example, 5' 7.5" or 5' 7 1/2" are both valid measurements.

How do you multiply feet and inches?

Convert everything to inches first, perform the multiplication, then convert back to feet and inches. Alternatively, convert to decimal feet, multiply, then convert back.

What's the difference between decimal and fractional inches?

Decimal inches use decimals (like 7.75 inches), while fractional inches use fractions (like 7 3/4 inches). Both represent the same measurement.