In the browser

Sourcing trip calculator

Enter cash, miles, hours, and what you expect the haul to return. Nothing is sent anywhere. The arithmetic runs in your browser.

Cash spentTotal at the register ($)

Miles drivenRound trip, all stops

Cost per mileUse the current IRS rate ($)

Hours spentDriving + shopping + listing

Items boughtEverything in the cart

Items keptSurvived your condition check

Net per saleAfter fees and shipping ($)

Sell-throughShare you expect to sell (%)

Enter your numbers above.

What the calculator is doing

Four calculations you can run on paper. They are written out so you can check them, and so the method still works if the script never loads.

The arithmetic
Output	Formula
All-in trip cost	cash spent + (miles × cost per mile)
Cost per listable item	all-in cost ÷ items kept after condition check
Break-even sell-through	all-in cost ÷ (net per sale × items kept)
Profit per hour	((items kept × sell-through × net per sale) − all-in cost) ÷ hours

The three inputs people get wrong

Cost per mile

Default it to the current IRS standard mileage rate rather than a fuel-only figure. Fuel ignores tires, servicing, and depreciation, and using it will make long loops look cheaper than they are. The rate is republished each year on the IRS site.

Hours

Include listing. Photographing, writing, and posting a haul often takes longer than acquiring it. Leave that out and sourcing looks like a better job than it is. If you have never timed a haul, time one before you trust a profit-per-hour number.

Items kept, not items bought

What survived the kitchen-table check is the number to use. Everyone buys things they later reject. Using the purchased count understates the real cost of every item you later list.

What to do with the output

Cost per listable item sets your buy ceiling at the rack. If all-in is $6 an item, a $4 tag is not a $4 item.
Break-even sell-through is the risk gauge. Above roughly 60% and normal attrition will erase the trip.
Profit per hour is the number that should change Saturday. Cut a store. Shorten a loop. Stay home and list.

Log the output for six weeks and the pattern is hard to unsee. The full method is in the trip math. Building a sourcing route is what to do with the answer. If the haul itself was the problem, what to buy is next.

Is this sourcing calculator free?

Yes. No sign-up. Everything runs in your browser. No figures are transmitted or stored.

What cost per mile should I use?

The current IRS standard mileage rate for business use is the most defensible default, because it accounts for depreciation and maintenance rather than fuel alone. It is updated annually.

Should listing time count as part of a sourcing trip?

Yes. Inventory produces nothing until it is listed, so the hours spent photographing and posting belong to the trip that generated them. Dropping them is the usual reason sourcing looks better than it is.

What break-even sell-through is too high?

As a rule of thumb, above about 60% is fragile. It leaves no room for the items that get damaged, mispriced, or never sell. Above 100% the trip cannot break even at any sell-through.

Disclosure Thrift Routes is published by the team behind FlowLister, which turns item photos into a complete eBay listing: title, item specifics, sold-comp pricing, shipping, and publishing. We built it, so treat this as a disclosure, not a review. The guides and calculator work the same if you never open it.