Floor Area Calculator
Add every room with its width and length, and the floor area calculator gives a room-by-room area table and the total floor area. Use it as a floor plan area calculator for a whole home, and open any single room in the editor.
How to use it
Start from the example or clear it
The list starts with four example rooms. Edit them, remove them or add your own.
Enter each room’s width and length
Metric or imperial; switching units converts the sizes you typed.
Check the table
Each row shows the room’s area in both unit systems and its share of the total.
Design a room
The Design button opens that room, with its name, as a new project in the editor.
What the total includes
The total is the sum of the rooms you list, measured the way you measured them. It leaves out walls, and anything you did not list, such as hallways, closets or stairs, unless you add those as rooms too.
The share column shows how the space is divided: if the living room is 40% of the total, you can see that at a glance before deciding whether a bedroom is too small or a hallway too big.
For a home on two floors, list the rooms of both and give them names that say which floor they are on, such as “Bedroom (upstairs)”.
From a list of rooms to a drawn plan
Draw the whole home in the editor and it finds each room enclosed by walls and lists it in the area schedule with its area, followed by the total, so the table here and the plan can be compared room by room. Areas follow the project units: m² for metric projects and sq ft for imperial ones.
When it helps
Before drawing a whole plan
Rough out the rooms you want and see the total they add up to.
Checking a listing
Add up the room sizes from a listing and compare the result with the advertised figure.
Comparing two layouts
See how the same total is shared between living space, bedrooms and circulation.
Planning work room by room
Keep one table of areas for flooring, painting or heating, one row per room.
Frequently asked questions
How do I calculate the total floor area of a house?
Measure each room, multiply width by length for each, and add the results. Enter the rooms here and the calculator adds them up for you in both square meters and square feet.
Should I include hallways, closets and stairs?
Include them if you want the floor area of the whole home: add each as its own row. Leave them out if you only want the area of the main rooms. The calculator adds exactly what you list.
Can I list rooms that are not rectangles?
Split them into rectangles and list each part as its own row, or use the square footage calculator, which handles L-shapes.
Why does my total differ from a listing or a deed?
Official figures may include walls, balconies or shared areas, and the rules differ between countries. This calculator adds only the rooms you enter, as you measured them.
Can I open the whole list as one plan?
No. Each row opens one room in the editor. To plan the whole home, start a blank plan or a template and draw the rooms side by side.
Ready to plan your space?
It is free, runs in your browser and needs no account. Projects are saved privately on this device.