Free tool
Cost per unit calculator.
For soap, candles and anything made in batches. Includes the costs most makers leave out — freight-in, packaging, labor, overhead and rejected units — and suggests a price for your margin. Preloaded with the candle example from our guide.
True cost per sellable unit
$4.23
92 good of 100 made · 92% yield
Price at 50% margin
$8.46
Check it against what your market pays and your channel’s fees.
The “naive” number
$1.84
Materials ÷ units made — what most spreadsheets show. It leaves out freight, packaging, labor, overhead and rejects.
Want this worked out for every batch?
GodKey MFG builds cost per unit from what you actually paid — freight included — and spreads rejects over the good units, every time you complete a batch. Read the full cost per unit guide.
Make soap or candles? Try the soap cost per bar calculator or the candle cost calculator.
How do you calculate cost per unit?
Add up everything the batch cost — materials, the freight you paid to get them, sellable packaging, labor at a real wage and a share of overhead — then divide by the units you can actually sell, not the units you made.
Why divide by good units instead of units made?
Rejected units still cost money. Their cost spreads across the units that survived, so dividing by units made understates your real cost per unit.
What margin should I use?
It depends on your channel. Selling direct can work at a lower margin; wholesale, where a retailer takes about half the retail price, needs a higher one. CandleScience suggests roughly 25–50% as a workable range for candles.
Is my data saved?
No. The calculator runs in your browser and nothing is sent anywhere. Use “Copy a link” to keep or share a set of numbers.
Stop rebuilding your costs in a spreadsheet.
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