MainMarket Documentation
MainMarket is a real-time US grocery price intelligence platform. We track 70+ chains, ~528k canonical products, and ~17M store-level price observations, refreshed weekly via direct chain-API scraping.
The API is built for two audiences: autonomous agents shopping or comparison-pricing on behalf of users, and institutional researchers (hedge funds, journalists, government economists) tracking food inflation. Discovery endpoints (stores, chains) are free; data endpoints (prices, products, coupons, indices) are $0.01 per call via x402 wallet payment, internal token, or B2B key.
What can I do?
Find cheapest prices nearby
Geo-search stores within a radius, then pull current shelf prices for any product or UPC.
GET /v1/prices
Track grocery inflation
Pull monthly egg, soda, and income-tier basket indices with full BLS-style methodology.
GET /v1/indices/{slug}
Resolve a shopping list
Map fuzzy item names to canonical UPCs, retailer SKUs, and PDP URLs at a specific store.
POST /v1/chains/{slug}/resolve-list
Compare prices across chains
Pull one product's price from every major banner to find the cheapest chain for a SKU.
GET /v1/prices?chain={slug}
Find coupons & deals nearby
Pull active digital coupons and clippable promos within a radius, with live shelf prices joined for true deal price.
GET /v1/coupons?lat&lng&with_prices=true
Plan an in-store route
Combine a resolved shopping list with the store's frequency-ranked aisles to walk the floor in one pass.
GET /v1/stores/{id}/aisles
Monthly inflation snapshot
Pull all four published indices (eggs, soda, low-income basket, high-income basket) for a single month and region.
GET /v1/indices/{slug} ×4
Next steps
- Getting started — make your first call in under 60 seconds with no signup.
- Authentication — x402 wallet payments, internal tokens, and B2B API keys.
- Concepts — how stores, chains, products, pricing tiers, and indices fit together.
- API Reference — every endpoint, parameter, and response shape.