Reseller bankroll calculator.

Worked example

With the defaults, Strategy A buys $25 items that return $15 profit but take 45 days to sell: a 60% return per cycle, which is 8.1 cycles a year. Strategy B returns $6 on the same $25 (24%) but turns in 10 days, 36.5 cycles a year. Simple annual return is the per-cycle return times cycles per year: about 487% for A and about 876% for B. These are what the same money would earn if it could be re-spent at the same rate all year, which is exactly what a sourcing limit prevents. With the defaults ($500 start, 6 months, up to 100 items a week) the model ends at $3,260 for A and $11,018 for B. Change only the sourcing limit to 15 items a week and it flips: $3,260 for A and $2,762 for B, because when stock is the constraint, profit per item matters more than how fast the money turns. Both results come from invented inputs; neither is a forecast, and your real limit is the supply of good stock.

How the model works

Methodology. Each cycle spends bankroll on whole items (bankroll ÷ cost, rounded down, and no more than the sourcing limit × days ÷ 7). Each item earns its profit minus a holding cost of cost × yearly cost of capital × days ÷ 365. Leftover cash sits idle. After the cycle, the bankroll grows by the net gain (less any share you do not reinvest). Return per cycle = net per item ÷ cost; simple annual = that × 365 ÷ days; compounded annual = (1 + return)^{365 ÷ days} − 1, which is an upper bound that assumes unlimited stock and no unsold items. Annualised figures that exceed one billion percent are not shown.

The model assumes every item sells in exactly the days-to-turn you enter. Real inventory has a spread of times, which the sell-chance page models, plus slow items that need the hold or markdown decision. Turnover ties in with the days of inventory, sell-through and carrying cost tools. See the thrift flip profit calculator for the profit on one item.

Speed versus margin

Margin is profit ÷ cost on one sale. Speed is how many times per year you can repeat it. Return on capital is their product, so a 24% margin repeated 36 times can beat a 60% margin repeated 8 times. The catch is that fast turnover needs a steady supply of stock, extra handling time and tolerance for thin margins that fees can erase, so check profit per hour on the hourly-rate page as well.

How to use it well

Fill Strategy A with the kind of stock you buy now and Strategy B with a faster, thinner alternative you are considering, using profit per item after fees and shipping. Then set the sourcing limit to how many good items you can really find in a week; this one input usually decides whether the faster strategy is realistic. Treat the compounded figure as a ceiling and the end bankroll as an illustration of how capital turns, not a target. If the two strategies are close, the tie-breaker is time: check the hours each needs on the hourly-rate page.

What this tool does not cover

• Any real return. All figures follow from the margin and days you enter; they are not observed results.
• Unsold items, price cuts, theft, loss and chargebacks, unless you reduce profit per item to reflect them.
• Taxes on profit. General information only; see the IRS pages cited.
• Borrowed money and interest beyond the single yearly capital-cost rate.
• The time you spend. Pair it with the hourly-rate calculator.

Sources (retrieved October 2026)

• IRS About Schedule C (Form 1040): how self-employed sellers report profit or loss. Retrieved October 2026.
• eBay fee tables: final value fee percentage and per-order fee used as the default inputs. Retrieved October 2026. Rates differ by category and change, so check the page for your category.

Every other number on this page is an input you type or an assumption labelled as an example. Results vary, and nothing here is an income claim.

FAQ

How much money do I need to start reselling?

The page does not name a number. It shows how many whole items a bankroll buys at your cost per item and how that changes your first cycle.

Why can speed beat margin?

Return on capital is margin per cycle times cycles per year. A lower margin that repeats much more often can produce a higher annual return, provided stock and demand keep up.

What is capital turnover?

How many times a year your money is spent on stock and comes back as sales. Shorter days-to-turn means higher turnover.

Is the annualised return realistic?

Treat it as a ceiling. It assumes every item sells on schedule and that you can reinvest at the same rate all year.

What does the sourcing limit do?

It caps items bought per cycle, so a growing bankroll stops compounding once you cannot find more good stock.