For developers and AI agents
The ListMath API and MCP server
Everything on this site is available to your app: fee calculations for 12 marketplaces, comparisons, target prices, where-to-sell advice and the change log.
Endpoints
| POST /v1/advise | Where to list one item: eligibility, profit, price needed for a goal, payout timing |
| POST /v1/calculate | Itemized fees, payout, profit, margin and ROI (batch of up to 100 with /v1/calculate-batch) |
| POST /v1/compare | One price, every marketplace, ranked by what you keep |
| POST /v1/target-price | Lowest price per marketplace for a profit, margin or ROI goal |
| GET /v1/changelog | Reviewed fee and policy changes, with effective dates |
| GET /v1/marketplaces | Categories, options, official sources and verification dates |
Example
POST /v1/advise
{ "item_type": "sneakers", "condition": "used",
"expected_price": 120, "item_cost": 40, "goal": { "profit": 30 } }MCP server for AI agents
Free to try with no key (20 tool calls a day), listed in the official MCP Registry as io.github.davidemena-spec/marketplace-fees.
{ "mcpServers": { "listmath": { "type": "http", "url": "https://marketplace-fee-calculator-api.huggyworks.workers.dev/mcp" } } }Plans
Free to try, then $20, $50 and $150 a month by volume on RapidAPI. Every plan gets the same data. Need more? Email support@listmath.com.