What is the acreage of my land?
Pick the shape of the land and type its measurements in feet, yards, miles, metres or kilometres. The acreage calculator shows the area in acres, square feet, square yards, square metres and hectares.
- Acres
- 2.2957
In acres, the land measures 2.2957; in square feet, 100,000.
- Square feet
- 100,000
- Square yards
- 11,111.11
- Square metres
- 9,290.3
- Hectares
- 0.929
Acres: 2.2957. In acres, the land measures 2.2957; in square feet, 100,000.
How to calculate
Computes the acreage of a rectangular, triangular, trapezoid or circular plot from its measurements, or of an area typed in any unit, in acres, square feet, square yards, square metres and hectares.
Example with the default inputs (Shape of the land Rectangle or square, Length 400 ft, Width 250 ft): In acres, the land measures 2.2957; in square feet, 100,000.
Method: Area = length × width (rectangle), ½ × base × height (triangle), ½ × (a + b) × height (trapezoid), or π × d² ÷ 4 (circle); acres = square feet ÷ 43,560.
- The land is flat: the area is measured on a level plane, as a survey does, not along slopes.
- An acre is 43,560 square feet of the international foot, 4,046.8564224 m² exactly.
- A plot with an irregular shape can be split into rectangles, triangles and trapezoids, with the acreages added.
Worked examples
Each example is checked against the calculator on every build.
- Shape of the land Rectangle or square, Length 400 ft, Width 250 ft gives Acres 2.295684, Square feet 100,000, Square yards 11,111.111111, Square metres 9,290.304, Hectares 0.92903.Source: NIST Handbook 44, Appendix C (1 acre = 43,560 ft², 1 ft = 0.3048 m)
- Shape of the land Rectangle or square, Length 660 ft, Width 66 ft gives Acres 1, Square feet 43,560, Square metres 4,046.856422.Source: NIST Handbook 44, Appendix C: 1 furlong = 660 ft, 1 chain = 66 ft, 1 acre = 43,560 ft² = 4,046.8564224 m² (international foot)
- Shape of the land I know the area, Area 107,639 ft² gives Acres 2.471054, Hectares 1, Square feet 107,639.104167.Source: NIST Handbook 44, Appendix C (1 hectare = 10,000 m²; 1 acre = 4,046.8564224 m²)
- Shape of the land Triangle, Base 300 ft, Height 200 ft gives Acres 0.688705, Square feet 30,000.
- Shape of the land Trapezoid, Top side 200 ft, Bottom side 300 ft, Height 150 ft gives Acres 0.860882, Square feet 37,500.
- Shape of the land Circle, Diameter 328.1 ft gives Square metres 7,853.981634, Acres 1.940761.
- Shape of the land Rectangle or square, Length 435.6 ft, Width 100 ft gives Acres 1.00005, Square feet 43,562.178.Source: NIST Handbook 44, Appendix C (1 acre = 43,560 ft²)
How it works
The calculator finds the area of the plot, then shows it in five units.
| Shape | Area |
|---|---|
| Rectangle | length × width |
| Triangle | ½ × base × height |
| Trapezoid | ½ × (top side + bottom side) × height |
| Circle | π × diameter² ÷ 4 |
The height of a triangle or trapezoid is measured at right angles to the base or to the two parallel sides. With I know the area, the calculator converts the area you type.
The units, all exact (international foot, 1 ft = 0.3048 m):
- 1 acre = 43,560 ft² = 4,046.8564224 m²
- 1 yd² = 9 ft² = 0.83612736 m²
- 1 ft² = 0.09290304 m²
- 1 hectare = 10,000 m²; 1 mi² = 640 acres; 1 km² = 100 hectares
Exact arithmetic. Each measurement is read as the exact decimal you typed, in the unit you typed it in: 12 ft 6 in is exactly 150 in, which is exactly 3.81 m. The page stores a measurement as a number in metres and reads it back as the decimal with the fewest significant digits, in one of the box's units, that gives the same stored number; a feet-and-inches pair counts by its value in inches (12 ft 6 in counts as 150, and 426.72 cm, exactly 14 ft, stays 426.72 cm), and on a tie the unit listed first in the box's unit menu wins. Every step except the circle's π is exact, so a result such as 1.00005 acres is exactly 1.00005 before it is rounded.
Rounding. Acres and hectares show with at most 4 decimals; square feet, square yards and square metres with at most 2. Each is rounded half up from its exact value (1.00005 acres shows as 1.0001), and trailing zeros are left off. A result shown with 15 or more significant digits (a very large value with its decimals) can differ from the exact value in its last shown digit, because the page keeps results as 64-bit floating-point numbers, which hold about 16 significant digits.
Assumptions
- The land is measured level, as a survey does, not along slopes.
- The shapes are exact: the rectangle has square corners, and the trapezoid's top and bottom sides are parallel.
- Each measurement is more than 0 and at most 1,000 km; a typed area is more than 0 and at most 10,000,000 km².
Worked examples by hand
A 400 ft by 250 ft lot. 400 × 250 = 100,000 ft². 100,000 ÷ 43,560 = 2.2957 acres. In metres: 100,000 × 0.09290304 = 9,290.30 m², which is 0.929 hectares; in square yards, 100,000 ÷ 9 = 11,111.11 yd².
A furlong by a chain. 660 ft × 66 ft = 43,560 ft² = 1 acre = 4,046.86 m².
One hectare. 10,000 m² ÷ 4,046.8564224 = 2.4711 acres, or 10,000 ÷ 0.09290304 = 107,639.10 ft².
A triangle with a 300 ft base and 200 ft height. ½ × 300 × 200 = 30,000 ft²; 30,000 ÷ 43,560 = 0.6887 acres.
A trapezoid with sides of 200 ft and 300 ft, 150 ft apart. ½ × (200 + 300) × 150 = 37,500 ft²; 37,500 ÷ 43,560 = 0.8609 acres.
A circle 100 m across. π × 100² ÷ 4 = 7,853.98 m²; 7,853.98 ÷ 4,046.8564224 = 1.9408 acres.
A tie at 4 decimals. 435.62178 ft × 100 ft = 43,562.178 ft², and 43,562.178 ÷ 43,560 = 1.00005 exactly, which shows as 1.0001 acres.
Other questions people ask
How many square feet are in an acre?
An acre is exactly 43,560 square feet. That is 4,840 square yards, or 4,046.8564224 square metres. Historically it was a strip one furlong (660 ft) long and one chain (66 ft) wide: 660 × 66 = 43,560.
How do I calculate the acreage of a lot?
Find the area in square feet and divide by 43,560. A rectangular lot 400 ft by 250 ft is 400 × 250 = 100,000 ft², and 100,000 ÷ 43,560 = 2.2957 acres. For a lot measured in metres, divide the square metres by 4,046.8564224.
How long is each side of a square acre?
The square root of 43,560 ft², which is about 208.71 ft (63.61 m). A square one acre in size is about 208.7 ft on each side.
How many acres is a hectare?
One hectare is 10,000 m², which is 2.4711 acres. One acre is 0.4047 hectare.
How do I find the acreage of an irregular plot?
Split it into shapes this calculator knows: rectangles, triangles and trapezoids. Find the acreage of each and add them. A plot with four straight sides that are not parallel can be split into two triangles along a diagonal.
Does a sloping plot have more acres?
No. Acreage is measured on a level plane, as a survey measures it, so a hillside counts by its footprint, not by the length of the slope. Measure the distances level, or use the lengths from a survey or a plat.