HOW THIS TOOL WORKS
Understand your result
Know the number of items you need to sell before you book the next event. This calculator uses the inputs above to produce a planning estimate. It does not predict sales or guarantee that the modeled price will work for your buyers.
Calculation formula
Contribution per item = selling price × (1 − fee rate) − variable cost. Required units = ceiling[(fixed event costs + extra profit target) ÷ contribution per item]. Round up because you cannot sell a fraction of an item.
Worked example
At a $25 price, $8 variable cost and 3% selling fees, each item contributes $16.25. With $225 of fixed event costs and no additional profit goal, you need 14 items to break even.
Before you rely on the estimate
- Use an average selling price when products have different prices, or model each product separately.
- If the contribution per item is zero or negative, increasing sales will not cover the fixed expenses.
- This measures a sales threshold, not the chance that visitors will actually buy.
Frequently asked questions
Why is the answer rounded up?
A whole item must be sold to cover the final portion of cost. Rounding down would leave you below the goal.
What is contribution per item?
The amount remaining from a sale after costs that rise with each sale, before fixed show expenses.
Can I plan for a specific profit?
Yes. Add that profit in the Extra profit target field.