Square Footage Calculator
Calculate area and material estimates
About the Square Footage Calculator
Whether you are buying flooring, ordering paint, or listing a property, you need the area of a space in square feet — and rooms are rarely a single simple rectangle. This calculator totals the area across multiple rooms, handles rectangular, circular, and triangular shapes, and even estimates the flooring and paint you will need.
Homeowners and renters measure rooms for renovations, real-estate agents total a floor plan, and DIYers size a project before buying materials. Adding rooms one by one and summing them means an L-shaped space or a whole apartment is handled in one calculation, with a built-in material estimate to take to the store.
How to Use the Square Footage Calculator
- Choose your units: feet, meters, or yards.
- Add each room, pick its shape (rectangle, circle, or triangle), and enter its dimensions.
- Read the total area across all rooms, plus the perimeter of rectangular rooms.
- Use the flooring and paint estimates, which add waste and coats, when buying materials.
Why Use ToolForge’s Square Footage Calculator
- It sums multiple rooms of different shapes in one go, so an irregular layout does not need separate calculations.
- It estimates materials — flooring with a 10% waste allowance and paint for two coats — turning area into a shopping list.
- It supports feet, meters, and yards and reports rectangular perimeters alongside area.
- It calculates locally with no account.
Frequently Asked Questions
How do I calculate the square footage of a room?
For a rectangular room, multiply length by width. For circular or triangular spaces the formulas differ, which is why this calculator lets you pick the shape. Add each room and it totals the combined area for you.
How much extra flooring should I buy for waste?
A common rule is to add about 10% for cuts, mistakes, and future repairs, which is exactly the allowance this calculator's flooring estimate uses. For complex layouts or diagonal patterns, you may want to add more.
How do I measure an L-shaped or irregular room?
Divide it into simple rectangles, add each as a separate room here, and the calculator sums them. Any outline can be broken into rectangles, circles, and triangles this way to get an accurate total.
Why does the paint estimate assume two coats?
One coat rarely gives even, full coverage, so painters typically apply two — which is why the paint estimate doubles the area. If you are using a primer or a one-coat paint, you can scale the figure down accordingly.
