How to calculate the total square footage of multiple rooms
To calculate the total square footage of multiple rooms, measure each room's length and width, multiply them for each room's area, then add the rooms together. The Multiple Rooms Square Footage Calculator sums those areas into one total in square feet (ft²).
Enter one row per room, hallway, or closet that belongs in the total. A 120-square-foot room and a 200-square-foot room combine to 320 square feet. Name rows when the takeoff must map back to a floor plan.
This page owns summing several spaces. The room calculator owns a single generic room method without multi-row totals.
Adding rooms of different shapes
Rectangular rooms use length × width on each row. Irregular rooms divide into rectangles first, then enter each rectangle as its own row or combine the section areas before entry. Add every valid row for the combined total.
Use the irregular shape calculator when a single odd outline needs a split-and-add walkthrough before the sum. Keep units consistent across rows so feet and meters are not mixed in one total.
Hallways and closets that receive the same finish should appear as their own rows. Skip outdoor spaces unless the project scope includes them.
Total square footage of an apartment or whole house
This tool sums any set of interior spaces: an apartment, one floor, or a whole house. Apartments are measured by interior finished space room by room. For real-estate rules on what counts as living area in a house, use the house calculator.
Add finished rooms on each floor, then total the floors when the project is a full house takeoff. Exclude garages and unfinished areas when the goal matches listing living area. Open the house calculator for ANSI Z765 include and exclude rules.
Office suites and retail demised spaces use the same sum-of-rooms method. Label each row so the combined total stays auditable against the plan.
Convert the combined area
Convert the combined square footage to square meters with × 0.0929. A 320-square-foot total equals about 29.7 square meters. Divide by 9 for square yards when a supplier quotes yd².
A 320-square-foot total equals 29.7 m² or 35.6 yd².
Use the square yards calculator for any area.
Use the square yards calculator for two-way conversions after the rooms are summed. Keep waste factors on material tools rather than inside the raw room total when comparing plan area to order quantity.
Recalculate the sum when any room dimension changes so the converted units stay aligned with the source takeoff.
Multiple rooms square footage calculator summary
The Multiple Rooms Square Footage Calculator finds the total square footage of multiple rooms by measuring each space, multiplying length by width, and adding the areas. A 120-square-foot room plus a 200-square-foot room equals 320 square feet.
Handle irregular rooms by dividing them into rectangles first. Use the house calculator for living-area rules, then convert the combined total to square meters or square yards as needed.