How the calculator works
You give it five things: how many watches you move a month, a typical sale price, the margin you aim for, how buyers usually pay, and what prep costs per watch. It splits the gross spread into the part you keep and the part that leaks to fees, service and shipping, then scales that to a month and a year. The admin hours are priced separately at whatever your time is worth.
The formula
- Gross spread per watch = sale price × target margin
- Leak per watch = (sale price × payment fee %) + prep and shipping
- True net per watch = gross spread − leak
- Monthly = per-watch figure × watches per month; yearly = monthly × 12
A worked example
Ten watches a month at $18,000 with an 18% target margin is a $3,240 gross spread per watch, or $32,400 a month. If buyers mostly pay by card (about 3%, or $540) and prep runs $300, the leak is $840 a watch. True net is $2,400, about 26% thinner than it looks. Across a year that’s roughly $100,000 of profit that only ever existed on the spreadsheet.
Payment method is the biggest lever. Move the same buyers to wire and the fee drag nearly disappears; list on a marketplace and it can triple. Our eBay vs Chrono24 fee calculator breaks that out per channel, and gross vs net profit for watch dealers explains why the gap matters at tax time. For benchmarks, see watch dealer profit margins.
What it leaves out
Overhead that isn’t per deal (rent, insurance, subscriptions), the cost of money tied up in aged stock, and trade-in gains or losses. Those belong in a real P&L. If you want the full picture, that’s what WristBook’s accounting builds from your deals automatically.