Calculate the area of a rectangle from length and width. Estimate square feet, square inches, square yards, square meters, perimeter, diagonal, material quantity, waste, and project cost.
Length and width:
The calculator converts both measurements to feet, then multiplies length by width to find square footage.
Perimeter:
The calculator adds length and width together, doubles the result, and shows the total distance around the rectangle.
Diagonal:
The calculator uses the Pythagorean theorem to estimate the corner-to-corner diagonal measurement.
Material estimate:
The calculator adds your waste percentage, divides by coverage per unit, and estimates total project cost.
A rectangle area calculator helps estimate the size of rectangular spaces for rooms, floors, walls, patios, concrete slabs, gardens, lawns, roofs, and land measurements.
It can help calculate square footage, compare area units, estimate material quantity, add extra waste, and estimate the cost of materials.
Your result shows the rectangle area, perimeter, diagonal, area with extra waste, estimated pieces or units needed, and estimated cost based on the values you enter.
Multiply the rectangle length by the rectangle width. For example, a 12 foot by 8 foot rectangle has an area of 96 square feet.
The formula is Area = Length × Width.
Add the length and width together, then multiply by 2. The formula is Perimeter = 2 × (Length + Width).
Use the formula Diagonal = √(Length² + Width²). This gives the corner-to-corner distance.
Yes. For flooring, tile, pavers, sod, fabric, and many construction materials, adding 5% to 15% extra is common for cuts, mistakes, and layout waste.