Start with usable yield, round purchases to packs and plan replenishment. Start with repair orders, parts invoices and technician time logs. Each example below uses hypothetical values you can replace.
Which calculator should you use?
| Tool | What it answers | What to check |
|---|---|---|
| Usable Material Cost | Account for cutting waste or unusable stock before pricing delivery. | Yield must be greater than zero. Keep purchased and usable quantities in the same measurement unit. |
| Material Order in Whole Packs | Round a material requirement to actual purchasable packs. | Apply waste before rounding. The allowance adds to net need; it is not a percentage loss from purchased quantity. |
These tools answer different questions and may use different units. Choose the tool that measures what you need; a larger result does not necessarily mean a better outcome.
Usable Material Cost
Account for cutting waste or unusable stock before pricing delivery.
Cost per usable unit = purchase cost / (purchased units × usable share)
Show example inputs and result
| Purchased material cost | 1,000 |
|---|---|
| Purchased units | 100 |
| Usable share | 90 % |
Result: 11.1111 per usable unit.
Yield must be greater than zero. Keep purchased and usable quantities in the same measurement unit.
Open usable material costMaterial Order in Whole Packs
Round a material requirement to actual purchasable packs.
Packs = ceiling(net quantity × (1 + waste) / pack quantity)
Show example inputs and result
| Net quantity needed | 86 |
|---|---|
| Waste allowance | 10 % |
| Units per supplier pack | 12 |
Result: 8 packs.
Apply waste before rounding. The allowance adds to net need; it is not a percentage loss from purchased quantity.
Open material order in whole packsUse the results in your plan
For a auto repair business, review parts, technician time, and shop overhead across the complete workflow. Use one consistent period and delivery unit: a repair order. Compare the assumptions with recorded outcomes after delivery, then update the estimate.
Explore all relevant auto repair calculators