How to Use This Calculator
Select Rectangle for standard rooms, bedrooms, and living areas. Enter length and width in feet, measured wall to wall. The Quantity field multiplies one room's area by the number of identical rooms — useful when ordering flooring for several same-size bedrooms in one shot. Enter a price per square foot to get an exact material cost. The 10% waste factor result is what you should actually order, not the base square footage. For L-shaped or irregular rooms, use the calculator twice for each rectangle and add the results. Closets count — include them in your measurement if you're flooring the whole room.
How to Calculate Square Footage of a Room
The formula is simple: square feet = length × width. Measure the length of the room from wall to wall in feet. Measure the width from wall to wall in feet. Multiply the two numbers together.
Example: a bedroom that is 13 feet long and 11 feet wide. 13 × 11 = 143 square feet. To order flooring with a 10% waste factor: 143 × 1.10 = 157.3 square feet. Round up to 158 square feet to order. If laminate cartons cover 22 square feet each, you need 158 ÷ 22 = 7.2 cartons — buy 8.
Measure in at least two places along each wall. In older homes, rooms are rarely perfectly square. Walls bow, floors slope, and corners drift from 90 degrees. Always use the longer of your two measurements. Ordering short is a far bigger problem than ordering slightly extra — a second order from a different production batch may not match your first shipment.
Room Measurement Tips
Include closets. Flooring runs into closets in almost every residential installation, and they're easy to forget when measuring. Measure the closet separately and add its area to the room total. A standard 2 × 4 foot reach-in closet adds 8 square feet — small but real.
Increase your waste factor for diagonal layouts and complex rooms. A standard 10% waste factor works for straight-run flooring in rectangular rooms. Tile installed at 45 degrees, or hardwood in a room with a bay window and multiple doorways, easily needs 15% to 20% waste. The extra boxes cost less than running short and special-ordering from a discontinued batch.
Buy all material from the same production batch. Hardwood, laminate, and tile all have batch or lot numbers on the carton. Colors, textures, and finishes can vary between production runs — often subtly but noticeably once installed. If you run short and reorder, the new cartons may not match. Buy one extra box as a permanent repair reserve.
What to Buy
For laminate: Pergo and Shaw both sell in cartons covering 18 to 25 square feet each. Calculate total area with waste, divide by carton coverage, round up to the nearest whole carton, then add one more for repairs.
For carpet: Shaw and Mohawk are the two largest residential brands. Carpet is priced by the square yard. Divide your square footage by 9 to convert. A 150 square foot room is 16.7 square yards — order 17 square yards. Ask the retailer before comparing quotes whether they're pricing in square feet or square yards. The same room looks like two very different numbers, and mixing units is an easy and expensive mistake.