Know your margin
before you buy.
Every time.
ResellerOS retrieves marketplace data via official APIs where available (including pricing and listing metadata), applies platform-specific fees, and surfaces your real net profit — before you spend a dollar.
How it works
From API query to confident sourcing decision in under 90 seconds.
Query the market
Enter a keyword, UPC, ASIN, or model number. ResellerOS queries official marketplace APIs and returns live, authorised pricing data in seconds.
Analyse your profit signal
Sort by estimated net profit or ROI. Platform fees, shipping costs, and your COGS are factored in live — giving you the real margin, not the headline price.
Track & act on winners
Save high-margin candidates to your watchlist. Recheck live API data at any time and see exactly how margins have shifted — so you act before the window closes.
Everything a reseller actually needs
Not a marketplace. Not a listing tool. A sourcing analytics platform built specifically to support arbitrage decisions.
Multi-Channel Profit Analysis
Enter a product name, UPC, or ASIN to retrieve authorised pricing data across your selling channels — fee-adjusted profit calculated instantly for each result.
Real Net Profit — Not Sticker Price
Every result shows platform fees, shipping costs, and estimated net margin — colour-coded so profitable opportunities stand out at a glance.
Watchlist & Price Monitoring
Save high-margin candidates and track price movements over time. One click to recheck live API data and see exactly how your margin has shifted.
Sourcing Decisions in Under 30 Seconds
Built for speed at the shelf or the screen. API queries run in parallel so you get a full profit picture fast — no manual lookups, no spreadsheets.
Official APIs — No Scraping, Ever
ResellerOS connects exclusively via eBay Browse API and Walmart Open API. No scraping, no unauthorised data collection. Every insight is derived from data you're authorised to access.
COGS & True Margin Calculator
Enter your cost of goods and every profit figure across all channels updates live — giving you an accurate arbitrage margin before you commit to a purchase.
Proof from early operator workflows
Real feedback from resellers who swapped their multi-tab setup for the hub.
“I can validate a product idea in under a minute now. Stopped opening 4 tabs at once.”
“The net and ROI view makes it easier to skip weak listings quickly. Way fewer bad buys.”
“My VA team moves faster because everything is in one consistent layout. Less context-switching.”
Built for where reselling is going
We're building the operating system for modern resellers — one phase at a time.
- Multi-market unified search
One search. eBay + Walmart results side-by-side instantly.
- Fee-adjusted ROI calculator
Platform fees, shipping & your cost calculated live.
- Arbitrage detection
Automatically surfaces buy-low/sell-high price gaps.
- Watchlist & price tracking
Save items and see price changes when you return.
- Sell-through rate estimation
Predict how fast an item will sell on each platform.
- Inventory tracking
Track your sourced items from buy to final sale.
- Historical price trends
See 30-day price history before making a buy decision.
- Amazon integration
Full Amazon FBA/FBM fee calculations and live prices.
- Auto-repricing
Automatically adjust your listing prices to stay competitive.
- One-click relisting
Relist items across multiple platforms with a single click.
- Bulk arbitrage scanner
Scan entire categories for hidden arbitrage opportunities.
- P&L dashboard
Full profit & loss tracking across all your platforms.
Marketplace coverage
Current support and planned expansion. Coverage depends on official API availability.
Browse API · Fee-adjusted profit · All conditions
Open API · Real-time prices · New + Refurb
FBA/FBM fees · ASIN search · In progress
We only add platforms when an official API is available — no scraping, no ToS violations.
Simple, transparent pricing
Start free. Upgrade when you need more.