Feet-Inch to Decimal Chart
Convert inches to decimal feet and tape-measure fractions to decimals. Use the converter for any measurement, like 7' 5 3/8".
Inches to decimal feet
Divide inches by 12. Many plans, spreadsheets and estimating programs want decimal feet, while tapes read in inches.
| Inches | Feet (4 dp) | Feet (2 dp) |
|---|---|---|
| 0" | 0.0000 | 0.00 |
| 1" | 0.0833 | 0.08 |
| 2" | 0.1667 | 0.17 |
| 3" | 0.2500 | 0.25 |
| 4" | 0.3333 | 0.33 |
| 5" | 0.4167 | 0.42 |
| 6" | 0.5000 | 0.50 |
| 7" | 0.5833 | 0.58 |
| 8" | 0.6667 | 0.67 |
| 9" | 0.7500 | 0.75 |
| 10" | 0.8333 | 0.83 |
| 11" | 0.9167 | 0.92 |
| 12" | 1.0000 | 1.00 |
Fractions of an inch to decimals and mm
| Fraction | Decimal inch | Decimal foot | mm |
|---|---|---|---|
| 1/16" | 0.0625 | 0.0052 | 1.59 |
| 1/8" | 0.1250 | 0.0104 | 3.17 |
| 3/16" | 0.1875 | 0.0156 | 4.76 |
| 1/4" | 0.2500 | 0.0208 | 6.35 |
| 5/16" | 0.3125 | 0.0260 | 7.94 |
| 3/8" | 0.3750 | 0.0312 | 9.52 |
| 7/16" | 0.4375 | 0.0365 | 11.11 |
| 1/2" | 0.5000 | 0.0417 | 12.70 |
| 9/16" | 0.5625 | 0.0469 | 14.29 |
| 5/8" | 0.6250 | 0.0521 | 15.88 |
| 11/16" | 0.6875 | 0.0573 | 17.46 |
| 3/4" | 0.7500 | 0.0625 | 19.05 |
| 13/16" | 0.8125 | 0.0677 | 20.64 |
| 7/8" | 0.8750 | 0.0729 | 22.22 |
| 15/16" | 0.9375 | 0.0781 | 23.81 |
How to convert any measurement
Feet-inch → decimal feet: turn the fraction into a decimal, add it to the inches, divide by 12 and add the feet. For example, 7' 5 3/8" → 3/8 = 0.375 → 5.375 in ÷ 12 = 0.4479 → 7.448 ft.
Decimal feet → feet-inch: keep the whole feet, multiply the decimal part by 12 for inches, then multiply the leftover decimal inch by 16 and round to get sixteenths. For 7.448 ft: 0.448 × 12 = 5.376 in; 0.376 × 16 = 6.0 → 6/16 = 3/8, giving 7' 5 3/8".
Where people go wrong
Decimal feet are not feet-and-inches written with a dot. 7.5 ft is 7' 6", not 7' 5". 7.10 ft is 7' 1.2", not 7' 10". When a drawing says 7.10', check whether it means decimal feet. Surveys and civil plans usually do.
Rounding matters too. Two decimal places of a foot is about ⅛" of precision (0.01 ft = 0.12 in), which is fine for estimating but too coarse for finish carpentry. Use four decimals, or stay in sixteenths, for cuts.
When to use decimal feet vs fractions
Decimal feet are easiest for anything you'll multiply: areas, volumes, material takeoffs and spreadsheets. Fractions are what you need at the saw and on the tape. A good routine is to measure in feet-inches-fractions, convert to decimal feet to estimate quantities, and convert back only when you mark a cut. Metric users can skip the chart. Multiply inches by 25.4 for millimetres, which is exact by definition.
Related
FAQ
What is 6 inches in decimal feet?
0.5 ft (6 ÷ 12).
What is 3/8 inch as a decimal?
0.375 in, which is 9.53 mm.
Is 7.10 feet the same as 7 feet 10 inches?
No. 7.10 ft is 7 ft 1.2 in. 7 ft 10 in is 7.833 ft.