SoldSync — Reseller Inventory & Oversell Tracker

Track what you've listed where across eBay, Poshmark & Mercari and never accidentally sell the same item twice.

Selling the same item on more than one marketplace? SoldSync makes sure you never sell it twice. SoldSync is a lightweight inventory tracker for resellers who cross-list on eBay, Poshmark, and Mercari. Log each item once, mark where it's listed, and when it sells on one platform SoldSync instantly reminds you to delist it everywhere else — before a double sale wrecks your seller rating. ✅ WHAT IT DOES • Simple inventory list — title, cost, list price, and which marketplaces each item is on. • Oversell guard — mark an item "Sold on eBay" and SoldSync flags every other platform it's still live on, so you can delist fast. • Add from this page — open a listing on eBay/Poshmark/Mercari and pull the title & price in one click. • Profit calculator — instant net profit after marketplace fees (eBay, Poshmark, Mercari, Depop, Etsy). 🔒 PRIVATE BY DESIGN Everything is stored locally in your browser. No account, no server, no data collection. SoldSync only reads a page when you click "Add from this page". 🪶 LIGHTWEIGHT No background processes, no auto-delisting (so it can't get your marketplace accounts flagged). It just helps you keep track. Free to use. Built for resellers, by people who hate canceling orders.