Material Utilisation Calculator
How many parts a sheet or bar yields, the material actually used against the material bought, and what the offcuts cost — the arithmetic behind nesting.
Parts per sheet is the floor of sheet length over part length times the floor of sheet width over part width, less the kerf on every cut.
How the material utilisation calculator works
Parts per sheet is the floor of sheet length over part length times the floor of sheet width over part width, less the kerf on every cut. Everything that is not a part is waste, and it is paid for at full price.
Rotating the part, or choosing a sheet size that divides evenly, often recovers 10 to 20% of the material. That is the whole business case for nesting software.
Formula: parts = floor(L / (l + kerf)) × floor(W / (w + kerf)); utilisation = parts × part area / sheet area
Worked examples
| Inputs | Parts per sheet | Note |
|---|---|---|
| 370 by 260 parts from a 2400 by 1200 sheet | 27 | about 80% utilisation |
| A part that divides evenly | 24 | 100% |
| A wide kerf | 24 | fewer parts, more waste |
FAQFrequently asked questions
What is material utilisation?
The share of a sheet or bar that ends up in parts. Everything else is offcut, and it was bought at the same price per kilogram as the parts.
What utilisation is good?
Above 80% for rectangular parts on rectangular sheets; nesting software on irregular parts reaches 70 to 85. Below 60% the material buyer should be asking questions.
What is kerf?
The width of material a cut removes — a saw blade, a laser beam, a plasma arc. Two to four millimetres for most sheet processes, and it comes out of every cut.
Why does orientation matter?
Because a part that leaves a 50 mm strip one way may leave a 250 mm strip the other. The page tries both; nesting software tries thousands of arrangements.
Can offcuts be used?
Sometimes, for smaller parts. Most shops have a rack of remnants that never get used, which is why the waste cost row is honest to count at full price.
Where these figures come from
- Nakajima (1988) — Introduction to TPM — the origin of Overall Equipment Effectiveness and its six big losses
- Safe Work Australia — the national work health and safety body
Last checked: September 2026. Definitions follow standard operations-management practice; where plants commonly differ, the page says so.