Free Square Footage & Area Calculator
Calculate area and perimeter for rectangles, circles, triangles, trapezoids, parallelograms, and ellipses. Supports ft, in, yd, m, cm, mm.
All calculations happen locally in your browser. No data is sent to any server. No signup, no tracking, no storage.
Square Footage Calculator — Free, Fast & Accurate
Our free square footage calculator helps you quickly determine the area of any room, property, or space. Whether you're planning a home renovation, installing new flooring, painting walls, or working on a construction project, this area calculator gives you instant results in square feet, square meters, and square inches. Enter your measurements in feet and inches or meters — the choice is yours.
Rectangle, circle, triangle, trapezoid, parallelogram, and ellipse — all in one tool.
Feet, inches, yards, meters, centimeters, millimeters — switch instantly.
Check "Calculate border only" to focus on perimeter — great for fencing, baseboards, and trim.
See the shape with dimension labels directly on the graphic.
All calculations are local. No data leaves your device.
Use instantly — no registration, no email, no payment.
How to Use This Area Calculator
1. Select the shape you want to measure.
2. Choose your preferred unit (ft, in, yd, m, cm, mm).
3. Enter the required dimensions — the input fields change based on the shape.
4. Check "Calculate border only" if you only need the perimeter.
5. Click "Calculate" to see the area and perimeter results, with the shape displayed on the right.
Formulas Used
- Rectangle: Area = length × width, Perimeter = 2(length + width)
- Circle: Area = π × radius², Circumference = 2π × radius
- Triangle: Area = ½ × base × height, Perimeter = side1 + side2 + side3
- Trapezoid: Area = ½ × (base1 + base2) × height, Perimeter = base1 + base2 + side1 + side2
- Parallelogram: Area = base × height, Perimeter = 2(base + side)
- Ellipse: Area = π × semi-major × semi-minor, Perimeter (approx.) = 2π × sqrt((a²+b²)/2)
Frequently Asked Questions
Learn how to use this tool correctly by reading our step-by-step tutorial.