Lot Size to Acres Calculator
Work out an area in acres from measured dimensions, for any common shape.
Area0.344353 aclength x width
Square metres1,393.546 m²
Square feet15,000 ft²
Acres0.34435
ShapeRectangle / squareLength: 150 ft · Width: 100 ft
The same area in other units
| Unit | Area |
|---|---|
| square meter | 1,393.55 m² |
| square foot | 15,000 ft² |
| square yard | 1,666.67 yd² |
| acre | 0.344353 ac |
| hectare | 0.139355 ha |
| square kilometer | 0.00139355 km² |
| square mile | 0.00053805 mi² |
The formulas
- Rectangle:
A = length × width - Circle:
A = π r², whereris half the diameter - Triangle:
A = ½ × base × height, where the height is measured perpendicular to the base - Triangle from three sides: Heron's formula,
A = √(s(s−a)(s−b)(s−c))withs = (a+b+c)/2 - Trapezoid:
A = ½(a + b) × height - Ellipse:
A = π × ½long × ½short
Awkward shapes
Real plots and rooms are rarely one clean shape. The usual approach is to split the outline into rectangles and triangles, measure each, and add the areas — subtracting any parts that are cut out. For a plot with four unequal sides and no right angles, split it along a diagonal into two triangles and use the three-sides option on each.
Watch the units
Areas scale with the square of a length, which is why the numbers surprise people: doubling both sides of a room quadruples its floor area, and there are 9 square feet in a square yard rather than 3.