How much extra flooring should I buy?

Add 10% for standard installs and 15% for diagonal or herringbone patterns to cover cuts and mistakes.

How do I measure an irregular room?

Break it into rectangles, calculate each area separately, then add them together before applying waste.

How many boxes of flooring do I need?

Divide your total square footage (with waste) by the coverage printed on the box, then round up.

How do you calculate square feet for flooring?

Measure the length and width of the room in feet and multiply them for the flooring area. For L-shaped rooms, split them into rectangles, find each area, and add them. Then add 10% for waste to get the square footage to buy.

Can I use this as a vinyl plank flooring calculator?

Yes. Enter the room size and set the coverage per box from your carton — it works for vinyl plank, laminate, engineered, and hardwood flooring types.

How to Install Flooring

Learn how to install flooring step by step, with the tools, materials, and a free calculator to estimate exactly what you need. To find how much flooring you need, use this square footage calculator for flooring: multiply the room length by width for the total square footage, then add 5–15% for waste and cuts. Divide by the coverage per box to get the number of boxes. A 15×12 ft room needs about 198 sq ft with 10% waste, costing roughly $600–$2,000 installed depending on material. It works for laminate, hardwood, and vinyl plank flooring.

Get exact numbers

Use the free Flooring Calculator to estimate your project.

Open calculator

Step-by-step

1
Measure the room
Multiply length × width. Split L-shaped rooms into rectangles and add them.
2
Add a waste factor
5% for straight lay, 10% standard, 15% for diagonal or patterned layouts.
3
Divide by box coverage
Check the carton — most boxes cover 18–24 sq ft.
4
Round up
Always round boxes up and keep a spare for future repairs.

Pro tips

Avoid: forgetting the waste factor — Cuts at walls and around obstacles waste material. Add 10% for straight lay and 15% for diagonal or herringbone.
Avoid: measuring an l-shaped room as one rectangle — Split irregular rooms into rectangles, calculate each, and add them before applying waste.
Avoid: not buying a spare box — Dye lots change between runs. Keep an extra box sealed for future repairs so it matches.
Avoid: ignoring underlayment and transitions — Underlayment, trim, and transition strips add to the budget and aren't in the flooring square footage.