Material Yield & Cut List Calculator
Count how many pieces come off a stock bar once the saw kerf is subtracted, see the drop left over, and find how many bars a required quantity needs.
The math behind a cut list
Yield is where a lot of material quietly goes to waste. Every cut removes a kerf’s worth of metal, and whatever’s left at the end of the bar that’s too short to use is drop. Counting both tells you the true number of pieces per bar and how many bars a batch will eat — the difference between ordering enough and coming up one part short.
Turn the drop and part weights into money with the Metal Cost Estimator, and get per-piece weight from the Metal Weight Calculator.
Frequently Asked Questions
How many pieces do I get from one stock bar?
It's the stock length divided by the piece length plus the kerf, rounded down. The kerf matters because every cut turns a slice of metal into chips. For n pieces you need n × piece length + (n − 1) × kerf of stock — the last piece has no trailing cut — so the calculator uses n = floor((stock + kerf) / (piece + kerf)).
What is kerf and why does it matter?
Kerf is the width of material removed by the blade on each cut, typically 1–3 mm depending on the saw. Ignore it and your cut list comes up short: on a 6 m bar cut into 500 mm pieces, a 3 mm kerf still costs you enough over eleven cuts to matter. Enter the real kerf of your saw for an honest count.
What is the drop or offcut?
The drop is the length left on the bar after the last usable piece — stock length minus the pieces and the kerfs between them. A high drop percentage means the piece length divides poorly into the stock; sometimes a different stock length, or nesting a shorter part into the offcut, cuts waste.
How many stock bars will my job need?
Enter the total pieces you need and the calculator divides by the pieces per bar and rounds up, so you buy enough. Real yield drops a little further with blade wander, clamping loss, and squaring the bar ends, so it's wise to add a bar or two of margin on a critical run.
Educational estimate assuming square cuts and a constant kerf. Real yield drops with blade wander, clamping, and end trim — add margin on critical runs.