Free Tool
Free hardwood floor calculator
Enter your room size and get the square feet, boxes, flooring cleats, and moisture paper for a nail-down hardwood floor, waste built in. Free, no signup.
10% diagonal, 15% herringbone
Private by design — everything you type stays in your browser. Nothing is uploaded, stored, or seen by us.
Solid wood moves, so plan for it
Nail-down hardwood fastens to the subfloor with cleats, over a layer of rosin or felt paper that slows moisture from below. The calculator sizes the paper at the room area and estimates the cleats.
Order the square feet shown, not the room size. Milling variation and cull boards mean you set aside pieces, so an 8 percent allowance is a safe start. Order a little extra to sort for color across the room.
The step people skip is acclimation. Let solid wood sit in the room for a few days before you install, so it reaches the home's humidity. Skip it and the floor can cup or gap once the heat comes on.
Hardwood Floor Calculator questions
How much hardwood should I order?
Room area plus about 8 percent for cuts, milling variation, and sorting for color. The calculator does it and rounds up.
What goes under nail-down hardwood?
A layer of rosin or felt paper as a moisture and squeak barrier. The calculator sizes it at the room area.
Why acclimate the wood?
Solid wood expands and contracts with humidity. A few days in the room first prevents cupping and gaps later.
Is this really free?
Yes. No email, no signup, and nothing you type leaves your browser.
Turn the takeoff into a priced estimate
Werx takes your quantities and builds a branded estimate and proposal in one step, then tracks the real cost as you install. 14-day free trial, no credit card.
No credit card required · Free migration assistance · Cancel anytime
Disclaimer: These free tools and templates are provided for general information and estimating purposes only. All results — including quantities, material and cost estimates, load, sizing, and span figures, scores, and any guidance or warnings — are rough approximations that may not fit your specific project, site conditions, local building codes, or current prices. They are not engineering, architectural, structural, legal, financial, or other professional advice, and are not a substitute for a licensed engineer, architect, contractor, or other qualified professional. Always confirm quantities, sizing, and structural, electrical, mechanical, and code requirements with a licensed professional and your local authority having jurisdiction before purchasing materials or performing any work. Werx makes no warranty as to accuracy and accepts no liability for any decision made using these tools. Use at your own risk. See our Terms of Service.