Lumber Cut List Calculator

You need 80 feet of base molding from 16-foot sticks. Buy six and you waste 16 feet. Buy five and you might come up short if any one piece has a defect you have to cut around. Buy seven "to be safe" and you've thrown $40 in trim into a corner.

A lumber cut list calculator runs the math the right way. It's a one-dimensional bin packing problem — fundamentally different from sheet good optimization, with different rules and different waste patterns.

1D vs 2D optimization: what makes linear materials different

Sheet goods are 2D: you arrange rectangles on a larger rectangle. Lumber, trim, and molding are 1D: you arrange lengths along a single axis (each stick).

The bin packing problem becomes simpler in 1D — but the practical complications are different:

  • Lumber has defects (knots, splits, twists) that you cut around
  • Long pieces only come from long sticks (no way to splice a 14' base trim from two 8' sticks)
  • Stock sizes are limited (8ft, 10ft, 12ft, 14ft, 16ft for dimensional lumber)
  • Some cuts need to be paired (left and right miters in a crown molding return)

EZNESTING's linear optimizer handles the math — the optimizer arranges your needed cuts onto available stock lengths to minimize total waste.

Worked example: 80 LF of crown molding from 16-foot sticks

A typical living room crown installation:

  • 4 pieces @ 14' (long walls)
  • 6 pieces @ 8' (short walls)
  • 8 pieces @ 4' (between corners and over windows)

Total need: 96 linear feet. From 16-foot sticks:

  • Stick 1: 14' + 2' waste
  • Stick 2: 14' + 2' waste
  • Stick 3: 14' + 2' waste
  • Stick 4: 14' + 2' waste
  • Stick 5: 8' + 8' (split)
  • Stick 6: 8' + 8' (split)
  • Stick 7: 8' + 4' + 4'
  • Stick 8: 4' + 4' + 4' + 4'

That's 8 sticks = 128 LF purchased, 96 LF used. ~25% waste. With 14' sticks (if available), the math changes — 6 sticks at 14' each = 84 LF, the 14' walls get cut clean, the rest comes from splits.

EZNESTING figures this out for you. Specify your needed cut lengths, available stock lengths, and the optimizer outputs the cut diagram per stick.

Planning around knots and defects

Real lumber isn't perfect. Even a "select" grade has occasional knots. The cut list optimizer can't see your sticks, so the standard workflow is:

  1. Mark defects as you receive the lumber — pencil a line through bad sections
  2. Order 5-10% extra beyond the optimizer's count
  3. Cut the visible/finish pieces first from the clearest material
  4. Use the off-cuts for paint-grade or hidden work

For framing lumber (studs, joists), defects are tolerated within structural limits. For trim, finish carpentry, and furniture, you cut around every visible defect. The optimizer's "minimum waste" answer assumes perfect stock — pad it.

Board feet vs linear feet: which one do you pay in?

Construction lumber is usually sold by the lineal foot for trim and molding (price per linear foot, e.g. $1.20/LF for base trim). Hardwood and rough lumber are sold by the board foot (BF = volume — length × width × thickness in inches, divided by 144).

A board foot is 1 sq ft of 1"-thick lumber. A 1×6 × 8ft board is 4 BF. A 1×4 × 8ft is 2.67 BF. The price-per-BF varies hugely — $4 for #2 pine, $14 for select red oak, $30+ for figured walnut or quartersawn white oak.

EZNESTING calculates linear yield (how many linear feet you need from your stock). For board-foot calculations, multiply: needed linear feet × board feet per linear foot of that profile.

When to use the linear optimizer vs the sheet optimizer

Linear: lumber, trim, molding, stair tread blanks, dowel rod, conduit, pipe, metal stock.

Sheet: plywood, MDF, melamine, ACM, sheet metal, glass.

EZNESTING has both — switch the mode toggle in the optimizer. A typical cabinet job needs both: sheet goods for the cabinet boxes (run through the plywood optimizer), and lumber for the face frames and doors (run through this linear optimizer).

Don't try to force 2D optimization onto 1D problems. The math gives the wrong answer.

Related guides

Frequently asked questions

How many studs per 16-foot board?
For 8-foot wall framing: two studs per 16-foot board (with about 2 inches of waste from the saw kerf). For 9-foot walls, the optimizer might pair an 8' stud with a 1' leftover header or jack stud cut. EZNESTING's linear mode lays this out automatically — input your needed stud lengths and stock board length, and it shows the cuts.
What is a board foot?
A board foot is 144 cubic inches of lumber — equivalent to a 1"-thick board, 12" wide, 12" long. Calculate it as (length in inches × width in inches × thickness in inches) / 144. A 1×6 × 8ft board is 4 board feet. Hardwood and rough lumber are sold by the board foot; construction lumber and trim are usually sold by the linear foot.
How much extra lumber should I order beyond the cut list?
5-10% for trim and finish carpentry, where you cut around every visible defect. 2-5% for framing where defects are tolerated. 15-20% for high-end work in figured hardwoods where you grain-match adjacent boards. The optimizer assumes perfect stock — real-world waste from defects, mistakes, and grain-matching adds on top.
Can I optimize a mix of stock lengths in one cut list?
Yes. Add multiple stock lengths (8ft, 10ft, 12ft, 14ft, 16ft) to the same project. The optimizer treats them as a pool and picks the best fit per cut. This is especially useful when long sticks are more expensive per foot — you can prioritize using up short stock first.
What's the best length to buy molding to minimize waste?
Depends on your longest required cut. If your longest piece is 13', buying 14' sticks gives you a clean cut with 1' of usable scrap. Buying 16' sticks gives 3' of scrap per long cut — usable for short pieces. Buying 12' sticks means splicing a 13' run, which is visible on trim. Match the stock length to your job; the optimizer can show you the math for each option.
How is 1D linear bin packing different from 2D sheet nesting?
1D bin packing arranges lengths along a single axis (a stick). 2D nesting arranges rectangles within a larger rectangle. The 1D problem is mathematically simpler — modern algorithms find optimal solutions quickly. The 2D problem is NP-hard, so optimizers find near-optimal solutions with reasonable compute time. EZNESTING uses different algorithms for each: First-Fit Decreasing for linear, modified guillotine and free-arrangement for sheet goods.