Area Calculator
Free Area Calculator: 8+ Shapes with Step-by-Step Results. Calculate square feet, square yards, and metric units for flooring, tile, paint, and landscaping projects.
Last updated: March 14, 2026
Enter Shape Details
Units
Choose Shape
Measurements
Use the simplest shape that matches the space. For odd layouts, break the area into a few smaller shapes, then add the totals.
Results
Calculation Steps
All Conversions
Good For
Need materials for this area? Jump to a project-specific calculator below.
How to Use This Area Calculator
1. Pick a shape
Start with the simplest shape that matches your room, yard, wall, or pad.
2. Enter dimensions
Use one unit system at a time. Feet and inches are best for most US home projects.
3. Check conversions
Use the output unit you need for materials, then sanity-check the other conversions.
Area Formulas & Calculation Steps
Rectangle
A = l × w
Triangle
A = (b × h) ÷ 2
Circle
A = πr²
Trapezoid
A = ((a + b) × h) ÷ 2
Parallelogram
A = b × h
Ellipse
A = πab
Sector
A = (θ ÷ 360) × πr²
Regular Polygon
A = n × s² ÷ (4 × tan(π ÷ n))
Source: standard geometry formulas used in construction, drafting, and measurement references.
For odd-shaped spaces, use this as a quick geometry check, then move to a project calculator for materials and waste.