How to Use
- 1.
Choose the first room's shape and measurement unit, then enter its dimensions.
- 2.
Add and label more rooms or sections; mark any closet, stair, or non-livable section as excluded when appropriate.
- 3.
Enable wall-thickness deduction only when dimensions were measured outside the relevant walls.
- 4.
Review the total in square feet, square meters, square yards, and acres plus the room breakdown chart.
- 5.
Enter flooring price, waste percentage, or paint coverage to estimate materials and compare options.
- 6.
Copy, share, save, or print the project, then verify measurements and product requirements before purchasing.
Features
Rectangle and square area
Triangle area
Circle radius or diameter
Trapezoid area
L-shaped room from two rectangles
Multiple labeled rooms and sections
Feet, inches, meters, and yards
Square feet, square meters, square yards, and acres
Excluded-space toggle
Wall-thickness deduction
Real-time totals
Room area breakdown chart
Flooring, carpet, and tile waste allowance
Material quantity and cost estimate
Three-option material comparison
Paintable-area and gallon estimate
Positive-value validation
Local project history
Copy and browser share
Print or save as PDF
Responsive dark-mode interface
Frequently Asked Questions
How do I calculate square footage?+
For a rectangular area, multiply length in feet by width in feet. For other shapes, select the shape and the calculator applies its correct area formula.
Can I calculate multiple rooms together?+
Yes. Add and label as many rooms or sections as needed. Included areas are converted to square feet and summed automatically.
How do I calculate an L-shaped room?+
Split it into two non-overlapping rectangles and enter the length and width of each part. The calculator adds both areas.
Can I enter measurements in meters or inches?+
Yes. Each section supports feet, inches, meters, or yards and is converted to a common square-foot total.
How do I exclude a closet or staircase?+
Add it as a labeled section and enable Exclude from total. Its measurement remains visible but is not added to the included area.
What does wall-thickness deduction do?+
It reduces supported room dimensions by twice the entered wall thickness before calculating area. Use it only when exterior measurements need an estimated interior adjustment.
How much extra flooring should I order?+
Many projects use a waste allowance, often around 5% to 15%, but the right amount depends on the layout, product, pattern, defects, and installer guidance.
Does the flooring estimate include labor?+
No. The material total uses waste-adjusted area and entered price per square foot. Add labor, delivery, underlayment, trim, taxes, and preparation separately.
Can floor square footage estimate wall paint?+
Not reliably. Enter actual paintable wall or ceiling area because floor area does not account for wall height, doors, windows, or number of coats.
How many square feet are in an acre?+
One acre contains 43,560 square feet.
Are these measurements valid for property records?+
Not automatically. Legal, appraisal, listing, tax, and construction measurement standards vary. Use the applicable standard or a qualified professional.
Can I save or export the project?+
Yes. Save locally in the browser, copy a summary, share the main assumptions, or print and save the result as a PDF.
About this tool
Free Square Footage Calculator
Use this free Square Footage Calculator to measure one room or combine multiple rooms and sections into a complete project. Choose feet, inches, meters, or yards, select the correct shape, and receive totals in square feet, square meters, square yards, and acres.
How the Square Footage Calculator Works
Add a room or section, choose its shape and measurement unit, then enter the required dimensions. The calculator converts every section to square feet before applying exclusions and optional wall-thickness deductions. Included areas are summed automatically, while excluded closets, stairs, or non-livable sections remain visible in the breakdown without increasing the project total.
Calculate Length Times Width in Square Feet
For a rectangle or square, area equals length multiplied by width. A room that is 12 feet long and 10 feet wide contains 120 square feet. Measurements entered in inches, meters, or yards are converted consistently before being added to the project.
Triangle, Circle, Trapezoid, and L-Shaped Areas
Triangle area equals one-half times base times height. Circle area equals pi times radius squared. Trapezoid area equals one-half times the sum of both parallel bases times height. An L-shaped room is modeled as two non-overlapping rectangles, which is often easier and less error-prone than trying to measure the missing corner.
Multiple Room Square Footage
Project mode lets you label and save separate living rooms, bedrooms, kitchens, hallways, garages, closets, or outdoor sections. Each room can use a different shape and unit. The area breakdown chart shows how much each included room contributes to the total.
Exclude Closets, Stairs, and Non-Livable Space
Turn on Exclude from total for areas that should be documented but not counted. This is useful when planning finished flooring, paint, taxable space, or livable area. Definitions of gross, net, finished, and livable square footage vary, so official property measurements should follow the relevant local or professional standard.
Wall Thickness Deduction
When dimensions were measured outside the walls, enable wall deduction and enter an estimated thickness. Rectangular dimensions are reduced on both sides before area is calculated. Complex plans, shared walls, varying construction, and official floor-area rules may require a detailed drawing or professional measurement.
Square Feet to Square Meters, Square Yards, and Acres
Results are displayed in common area units. One square yard equals 9 square feet, one square meter is approximately 10.7639 square feet, and one acre equals 43,560 square feet. Conversion does not change the physical area; it only changes how the result is expressed.
Flooring, Carpet, and Tile Cost Estimator
Enter a price per square foot and a waste allowance to estimate the material quantity and total cost. Waste helps account for cuts, pattern matching, breakage, and unusable offcuts. The appropriate percentage depends on room shape, material, installation pattern, and installer guidance.
Paint Coverage Estimator
The paint estimate divides entered paintable area by coverage per gallon and rounds up the purchase quantity. Floor area is not automatically the same as wall or ceiling paint area, so enter the actual paintable surface measurement for a useful estimate.
Compare Material Options
Enter up to three material names and prices to compare project totals using the same waste-adjusted area. This supports an initial budget comparison without implying labor, delivery, underlayment, taxes, or preparation costs are included.
Save, Copy, Share, and Print a Project
Save projects locally in the browser, copy a clear room-by-room summary, share the main project assumptions, or print the page and choose Save as PDF. Saved projects stay on the current device unless exported or shared.
Measure Before Ordering Materials
This calculator is a planning tool. Recheck dimensions, openings, exclusions, pattern direction, product coverage, package size, waste requirements, and installer recommendations before ordering materials or using the result for a legal property record.
After measuring a room, prepare image dimensions with the Image Resizer, compare percentage-based material allowances using the Percentage Calculator, or estimate a property's initial cash requirement with the Down Payment Calculator.