Seller Ledger

Cost/profit tracking, sales history, and local backups for your Facebook Marketplace Selling page. Read-only, no auto-posting.

Seller Ledger — Cost & Profit Tracking for Facebook Marketplace Sellers Facebook Marketplace never tells you what you actually made. It shows a price, but not what you paid for the item, not your running profit, and once a listing sells and disappears, there's no record left at all. Seller Ledger fixes that, right on your own Selling page — no spreadsheet, no separate app to remember. WHAT IT DOES • Cost & Profit — enter what an item cost you once; profit shows automatically next to the price, updating live. • Sales History — when a listing disappears from your Selling page, Seller Ledger logs it as sold: price, cost, profit, and days listed. No manual entry needed. • Expenses — log packaging, shipping, mileage, storage, and other costs that aren't tied to one item. • Tax Summary — Revenue, Cost of Goods Sold, Other Expenses, and Net Profit for this year, last year, or all time, with CSV export. Not tax advice — a real starting point for your own records or your accountant. • Archive & Remove / Backup Selected — saves a listing's photos and details to your Downloads folder before it comes down. • Duplicate Cleanup — flags listings with identical titles for review; nothing is deleted without your confirmation. • CSV export for inventory, sales history, expenses, and tax summary, independently. WHY IT MATTERS If you sell regularly, "I'll remember the numbers" stops being true fast. US payment platforms report gross payment volume on Form 1099-K once you cross the threshold — that number doesn't subtract what you paid for the item or your expenses, so without your own records you can end up owing tax on money that was never actual profit. Seller Ledger builds those records automatically, as you sell, instead of asking you to reconstruct them later. WHAT THIS IS NOT Seller Ledger does not create, edit, or relist listings, and does not automate posting in any way. It only reads the data already on your own Selling page, and only deletes a listing when you explicitly select it and confirm. YOUR DATA • Seller Ledger does not operate a server — there is nowhere for your data to be sent. • Cost, price, sales history, and expense entries stay in your browser's local storage. • No analytics, telemetry, or third-party reporting of any kind. • Data leaves your browser only when you export a CSV or use the local backup feature — both save to your own Downloads folder. Seller Ledger is an independent project, not affiliated with, endorsed by, or sponsored by Meta Platforms, Inc. "Facebook" and "Marketplace" are trademarks of Meta Platforms, Inc., referenced here only to describe what this extension works with. GETTING STARTED Install, sign in to Facebook as usual, open your Marketplace Selling page, and Seller Ledger scans your listings automatically. Enter a cost the first time you look at each one — everything else keeps itself up to date from there.