What is the total in feet and inches?
Enter lengths in feet and inches, such as 5 ft 7 1/2 in, and choose what to do with them. See the answer in feet and inches, rounded to the tape-measure fraction you pick.
- Result
- 8 ft 3 3/4 in
The result is 8 ft 3 3/4 in.
- In inches
- 99.75 in
- In feet
- 8.3125 ft
- In centimetres
- 253.37 cm
Result: 8 ft 3 3/4 in. The result is 8 ft 3 3/4 in.
How to calculate
Adds or subtracts two lengths in feet and inches, or multiplies or divides one by a number, and shows the result in feet and inches to the nearest fraction of an inch, in inches, feet and centimetres.
Example with the default inputs (First length 5 ft 7.5 in, Operation +, Second length 2 ft 8.25 in, Round to 1/16 in): The result is 8 ft 3 3/4 in.
Method: result = first ± second, or first × number, or first ÷ number; shown as feet, whole inches and the nearest fraction of an inch
- 1 ft = 12 in, and 1 in = 2.54 cm exactly.
- The feet-and-inches result rounds to the nearest fraction chosen; a value exactly halfway rounds up (away from zero). The inch, foot and centimetre results are not rounded.
- A negative result (a longer length subtracted) shows a minus sign in front.
- Zero feet or zero inches are left out of the feet-and-inches result (3 ft, 5/16 in); a result of zero is 0 in.
Worked examples
Each example is checked against the calculator on every build.
- First length 5 ft 7.5 in, Operation +, Second length 2 ft 8.3 in, Round to 1/16 in gives Result 8 ft 3 3/4 in, In inches 99.75 in.Source: hand calculation in content.mdx: 5 ft 7 1/2 in + 2 ft 8 1/4 in = 7 ft 15 3/4 in = 8 ft 3 3/4 in
- First length 3 ft 2 in, Operation −, Second length 4 ft 0.1 in, Round to 1/16 in gives Result −10 1/8 in, In inches -10.125 in.Source: hand calculation in content.mdx: 38 in − 48 1/8 in = −10 1/8 in
- First length 10 ft 0 in, Operation ÷, Number 2, Round to 1/16 in gives Result 5 ft, In inches 60 in.Source: hand calculation in content.mdx: 120 in ÷ 2 = 60 in = 5 ft exactly
- First length 7 ft 0 in, Operation ÷, Number 3, Round to 1/16 in gives Result 2 ft 4 in, In feet 2.3333 ft.Source: hand calculation in content.mdx: 84 in ÷ 3 = 28 in = 2 ft 4 in
- First length 0 ft 1 in, Operation ÷, Number 3, Round to 1/16 in gives Result 5/16 in.Source: hand calculation in content.mdx: 1/3 in = 5.33/16 in, which rounds to 5/16 in
- First length 6 ft 1.1 in, Operation ×, Number 2.5, Round to 1/8 in gives Result 15 ft 2 3/4 in, In inches 182.75 in.Source: hand calculation in content.mdx: 73.1 in × 2.5 = 182.75 in = 15 ft 2 3/4 in
How it works
- Convert each length to inches: feet × 12 + inches. Metric lengths use 1 in = 2.54 cm.
- Work out the result:
- Add: first + second.
- Subtract: first − second. The result can be negative.
- Multiply: first × the number.
- Divide: first ÷ the number.
- Show it in feet and inches. Take the size of the result in inches and round it to the nearest 1/d inch, where d is the fraction you chose (2, 4, 8, 16, 32 or 64). A value exactly halfway rounds up. Then:
- feet = the whole number of 12-inch lengths in it;
- inches = what is left, as whole inches and a fraction in lowest terms (for example 6/16 becomes 3/8).
- Zero feet are left out (5/16 in), zero inches are left out (5 ft), and a result of zero is 0 in.
- A negative result gets a minus sign in front.
The results in inches, feet and centimetres are exact, not rounded to a fraction.
A count of 1/d inches within 0.000000001 of a half counts as that half (float noise), so it rounds up. Each length can be up to 1,000 ft, and the number from 0.001 to 1,000.
Worked examples by hand
5 ft 7 1/2 in + 2 ft 8 1/4 in. 67.5 in + 32.25 in = 99.75 in. 99.75 ÷ 12 = 8 feet with 3.75 in left: 8 ft 3 3/4 in.
3 ft 2 in − 4 ft 1/8 in. 38 in − 48.125 in = −10 1/8 in.
10 ft ÷ 2. 120 in ÷ 2 = 60 in = 5 ft exactly.
7 ft ÷ 3. 84 in ÷ 3 = 28 in = 2 ft 4 in, or 2.3333 ft.
1 in ÷ 3, to 1/16 in. 1/3 in × 16 = 5.33, which rounds to 5, so 5/16 in.
6 ft 1.1 in × 2.5, to 1/8 in. 73.1 in × 2.5 = 182.75 in. 182.75 − 15 × 12 = 2.75 in, and 0.75 = 6/8 = 3/4, so 15 ft 2 3/4 in.
Other questions people ask
How do I add feet and inches?
Add the feet and the inches separately, then turn every 12 inches into a foot. 5 ft 7 1/2 in + 2 ft 8 1/4 in = 7 ft 15 3/4 in = 8 ft 3 3/4 in.
How do I subtract feet and inches?
Convert both lengths to inches, subtract, and convert back. 4 ft 1/8 in − 3 ft 2 in is 48 1/8 − 38 = 10 1/8 in. If the second length is longer, the answer is negative.
How do I divide a length into equal parts?
Choose ÷ and enter how many parts. 7 ft ÷ 3 is 84 in ÷ 3 = 28 in = 2 ft 4 in. When the answer is not a whole fraction of an inch, it rounds to the nearest one you chose.
How do I convert decimal inches to a fraction?
Multiply the decimal part by the denominator you want and round. 0.33 in × 16 = 5.3, which rounds to 5, so 0.33 in is about 5/16 in.
Why round to 1/16 of an inch?
Most tape measures in the US are marked in 1/16 in. Choose 1/32 or 1/64 for finer work, or 1/8 or 1/4 for rough framing.
Can I enter centimetres?
Yes. Pick cm, mm or m in the unit list for either length. The answer is still shown in feet and inches, and in centimetres.