How Many 2x4s Do You Need?

Building a deck, framing a wall, or constructing furniture? Our lumber cut calculator figures out the most efficient way to cut your boards - so you buy exactly what you need, not more.

Example: Deck Railing

Need 24 balusters at 36" each from 8-foot 2x2s? Naively, you might think you need 24 boards. But our optimizer shows you can get 2 balusters per board (with the kerf), so you only need 12 boards - saving 50%.

See exactly how to cut each board for maximum efficiency

Any Board Length

Works with 8', 10', 12', 16' boards - or any custom length you have.

Kerf Calculation

Accounts for saw blade thickness so your cuts actually fit on the board.

Multiple Lengths

Need different cut lengths? We optimize across all your required pieces.

Instant Results

See your optimized cut list immediately - no signup required.

Standard Lumber Sizes Reference

Nominal Size	Actual Size	Common Lengths
2x4	1.5" x 3.5"	8', 10', 12', 16'
2x6	1.5" x 5.5"	8', 10', 12', 16'
2x8	1.5" x 7.25"	8', 10', 12', 16'
2x10	1.5" x 9.25"	8', 10', 12', 16'
2x12	1.5" x 11.25"	8', 10', 12', 16'
4x4	3.5" x 3.5"	8', 10', 12'

Common Projects & Lumber Needs

Deck Building

Joists: 2x8 or 2x10, typically 16" on center
Decking: 2x6 or 5/4x6 deck boards
Posts: 4x4 or 6x6 for railings and support
Railings: 2x4 top/bottom rails, 2x2 balusters

Wall Framing

Studs: 2x4 at 92-5/8" for 8' walls (16" on center)
Plates: 2x4 top and bottom plates, wall length
Headers: 2x6, 2x8, or 2x10 depending on span

Workbench / Furniture

Legs: 4x4 posts or laminated 2x4s
Stretchers: 2x4 or 2x6
Top: Laminated 2x4s, 2x6s, or 2x10s

Pro Tips for Cutting Lumber

Check for straight boards - Sight down each board at the store. Reject warped or twisted ones.
Buy 10-15% extra - Some boards will have defects you need to cut around.
Consider longer boards - Sometimes 12' boards yield less waste than 8' boards, even if they cost a bit more.
Cut longest pieces first - Get the critical cuts done while you have full-length stock.
Mark your cuts - Use our printed cut list and check off each piece as you go.

Lumber Cut Calculator