Calculate carpet area for rectangle, circle, ellipse, pentagon, hexagon, or custom shapes, then estimate cost with a configurable waste allowance.
Carpet dimensions
Area = length × width
Cost calculations
Add ~10% extra for cutting mistakes and installation.
Formula
How to Calculate
Examples
About this calculator
The Carpet Calculator estimates carpet area and cost for rectangle, circle, ellipse, pentagon, hexagon, and custom shapes. It uses standard area formulas and includes a waste allowance so you order enough material for installation.
Six shape modes
Switch between rectangle, circle, ellipse, pentagon, hexagon, or enter a known area for irregular carpets and rugs.
Accurate area formulas
Uses standard geometry—πr² for circles, πab for ellipses, and regular polygon formulas for pentagons and hexagons.
Cost with waste
Enter price per sq ft or m² and apply a waste percent (default 10%) to estimate what you should budget and buy.
- Area rugs
- Wall-to-wall carpet quotes
- Odd-shaped rooms
- Budget planning
Frequently asked questions
Quick answers about this calculator—how it works, accuracy, and everyday use.
Choose your carpet shape, enter its dimensions to get the area, then multiply by the price per square foot (or square meter). This calculator also adds a waste allowance—typically 10%—so you buy enough for cutting and installation.
Rectangle, circle, ellipse, regular pentagon, regular hexagon, and other shapes (enter the area directly). For example, circle area = πr² and a regular hexagon uses area = (3/2)√3 × side².
Cutting mistakes, pattern matching, and irregular rooms often require more material than the exact floor area. Many installers recommend buying at least 10% extra, and this tool applies that waste allowance by default.
Yes. Choose Other shapes and enter the carpet area directly—useful for irregular rugs or when you already measured the floor with another area tool.