Market day inventory.

Worked example

300 customers stop at the booth and 40% buy this item, 1.5 units each: 300 x 0.40 x 1.5 = 180 units expected. A 15% buffer lifts the plan to 207 units, and 5% expected waste means bringing 207 / 0.95 = 217.89, rounded up to 218 units. At $1.80 a unit the stock costs $392.40. Selling the expected 180 units at $5.00 brings $900.00, a profit of $507.60 on this item, with 38 units left over.

How it works

Expected units = customers x share who buy x units per buyer. The buffer adds a margin for a busier day, and dividing by (1 - waste) allows for stock that spoils or is damaged before it can be sold. The result is rounded up to a whole unit.

Profit assumes you sell exactly the expected units and pay for everything you bring, so leftovers count as a cost. Use history from past markets where you have it; the tool has no built-in sales rate. Perishable items need extra care: follow your local health rules for holding and storing food. This is a planning estimate, not legal, licensing, tax or financial advice.

Sources and basis (checked 2026-10-08): Arithmetic on your inputs only. Customer counts, buying rates, buffers and waste are your own estimates; none are assumed.

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FAQ

How many should I bring to a farmers market?

Estimate expected units from customers, the share who buy and units per buyer, then add a buffer and allow for waste. The calculator does that and rounds up.

What buffer should I use?

It is your call. A larger buffer lowers the risk of selling out but raises the leftover stock you pay for. Compare buffers in the tool and look at the leftover units and stock cost.

What counts as waste?

Stock you expect to lose before selling it, such as spoilage, breakage or samples. It is separate from the buffer, which is stock you expect to be unsold.

Can I plan several items?

Run the tool once per item. Each item has its own buying rate, cost and price.