Math

Room Area Calculator

Calculate the Area of Any Room

Planning a renovation or buying flooring? Enter your room dimensions to calculate the total area. For rectangular rooms, simply enter the length and width. For unusual room shapes, select the closest geometric shape from the options.

A = l × w

Area Calculation Tips

Click to show tips

Try an Example

Pick a scenario to see how the calculator works, then adjust the values

Living Room Floor

Calculate the floor area of a 5m x 3m rectangular living room.

Key values: Rectangle · 5m x 3m · 15 m²

Circular Garden

Find the area of a circular garden bed with a 5-meter radius.

Key values: Circle · Radius: 5m · ≈78.54 m²

Triangular Plot (SSS)

Calculate the area of a triangular land plot with sides 3, 4, and 5 meters using Heron's formula.

Key values: Triangle (SSS) · Right triangle · 6 m²

Hexagonal Patio

Find the area of a regular hexagonal patio with 10m sides.

Key values: Regular Polygon · 6 sides · 10m per side

Documentation

This calculator is also known as Room Area Calculator.

Read the complete guide

Measuring Your Room

Tips for accurate room measurement:

Measure wall-to-wall at floor level, not at the ceiling
For L-shaped rooms, divide into two rectangles and add the areas
Include closets and alcoves if you need full floor coverage
Subtract the area of permanent fixtures you will not cover
Always add 10% waste factor for flooring materials

Examples

Bedroom Flooring

A rectangular bedroom measuring 4.2 m by 3.5 m needs new laminate flooring.

Area = 4.2 x 3.5 = 14.7 m squared (about 158.2 ft squared). With a 10% waste factor, order materials for 16.2 m squared.

Key takeaway: Always order 10% more flooring than the calculated area to account for cuts and waste.

Room Renovation Planning

Plan your room project efficiently:

Measure the room twice to confirm dimensions
Add 10% waste factor for flooring and 5-10% for paint
For L-shaped or irregular rooms, sketch the shape and divide into rectangles
Convert between units if your supplier uses different units than your measurements

Frequently Asked Questions about Room Area Calculator

How do I calculate the area of an L-shaped room?

Divide the L-shape into two rectangles. Measure the length and width of each rectangle separately, calculate their areas, and add them together. For example, if one section is 4 x 3 m and the other is 2 x 2 m, the total area is 12 + 4 = 16 m squared.