--- title: "API Reference: Core RateAPI Endpoints" description: "Core RateAPI REST endpoints for lending rates, deposit APYs, credit unions, eligibility, and decisions, with a link to the complete live OpenAPI spec." canonical: "https://rateapi.dev/api/reference" last-updated: "2026-09-27" source: "https://rateapi.dev/llms.txt" --- # API Reference: Core RateAPI Endpoints [Home](https://rateapi.dev/) / API Reference # API Reference Every public RateAPI endpoint in one place. 34 REST endpoints over real, ranked credit union rates — decisions, rate analytics, borrower tools, monitors, and reference data. Authenticate with your API key in the `X-API-Key` header. Get a Free API Key [View OpenAPI Spec (JSON)](https://api.rateapi.dev/openapi.json) The machine-readable contract lives at [https://api.rateapi.dev/openapi.json](https://api.rateapi.dev/openapi.json) . Use it to generate a typed client in any language. ## Rates & deposits Query current, evidence-backed lending APRs and deposit APYs. - GET `/v1/rates` Current lending rate rows filtered by product, state, term, occupancy, audience, and other documented query parameters. - POST `/v1/deposit-rates` Deposit APYs in list or benchmark mode. Send JSON field product_category with an exact underscore value: savings, cd, share_certificate, money_market, ira_cd, ira, or share_savings. - POST `/v1/deposit-beta` Retention-bounded deposit repricing sensitivity. Send JSON field product; money market is money_market. ## Decisions Rank real credit union offers for a borrower scenario and explain the result. - POST `/v1/decisions` Rank the best qualifying lender offers for a financing scenario. Optional borrower affinity inputs (employer, military_status, school, worship) and context.geo.county annotate each offer with a membership-eligibility verdict. - POST `/v1/decisions/batch` Run many decision scenarios in a single request. - POST `/v1/explain-ranking` Decompose why each top lender ranked where it did, with cost breakdowns. - POST `/v1/simulate-decision` Sweep one input (credit score, down payment, rate shift) and see the winner per value. ## Rate analytics Position quotes and watch how the live market distribution moves. - GET `/v1/stats` Headline coverage stats across the dataset. - GET `/v1/benchmarks` National and per-state benchmark APR distributions by product. - GET `/v1/rates/nearby?zip={zip}&product_type={product}` Rank current product-matched rates from the nearby-branch set by published APR, with source-labelled distance. REST counterpart to find_product_rates_near_zip. - POST `/v1/rate-sanity-check` Position an external quote in the live market distribution (percentile + classification). - POST `/v1/rate-delta` Compare the market APR distribution now vs ~1/2/4 weeks ago. - POST `/v1/competitive-position` See where a given rate sits against the live competitive set. - POST `/v1/buy-timing` Forward buy/refi-now vs wait lean from recent movement and break-even sensitivity. ## Borrower tools Affordability, monthly cost, refinance, and savings math grounded in real rates. - POST `/v1/affordability` Max monthly payment, loan amount, and home price from income and DTI caps. - POST `/v1/monthly-cost` Full monthly cost (PITI) estimate for a loan. - POST `/v1/refinance-break-even` Break-even months and lifetime savings for a refinance. - POST `/v1/scan-savings` Find the best refinance offer for each debt in a stack and quantify savings. - POST `/v1/advice-guardrails` Guardrail checks (DTI strain, long terms, balloon, stale data) over a scenario. ## Monitors Standing decision monitors that re-evaluate scenarios and fire webhooks on change. Scenarios are re-evaluated against your monitored band, not your exact figures. - POST `/v1/monitors` Create a decision monitor (borrower or competitor). - GET `/v1/monitors` List your monitors. - GET `/v1/monitors/{id}` Fetch a single monitor. - PATCH `/v1/monitors/{id}` Update a monitor. - DELETE `/v1/monitors/{id}` Delete a monitor. - POST `/v1/monitors/{id}/simulate` Dry-run a monitor against current rates without persisting. ## Membership eligibility Who can join each credit union — evidence-backed verdicts (open_to_anyone, likely_eligible, eligible_via_employer, eligible_via_military, geo_mismatch, unknown) and full field-of-membership records. - GET `/v1/credit-unions/{id}/eligibility` Full field-of-membership record: geo footprint, employers, associations, fees, provenance, and evidence URL. - POST `/v1/eligibility/check` Check up to 50 credit unions against one user profile (state, zip, county, employer, occupation, military_status, school, worship) and get per-CU verdicts with matched rule, join_cost_usd, and join steps. ## Reference data & keys Credit union directory, metadata, and API key management. - GET `/credit-unions` Search the credit union directory. - GET `/credit-unions/nearby?zip={zip}` Find credit unions ordered by estimated distance to each institution's closest NCUA-reported branch. REST counterpart to the find_credit_unions_near_zip MCP tool. - GET `/credit-unions/{state}/{slug}` Fetch a single credit union profile: all current rates plus a nullable eligibility object (who can join) — requirements summary, join paths, cost to join, and evidence URL. Annotates published criteria; never asserts an individual is ineligible. - GET `/meta` Dataset metadata: products, states, freshness. - POST `/keys` Provision a new API key. - GET `/keys/{keyId}/usage` Usage stats for an API key. - DELETE `/keys/{keyId}` Revoke an API key. ## Start building A free key gives you 20 requests/month (email required). Point your codegen at the live OpenAPI spec and you have a typed client in minutes. Get a Free API Key [Open the OpenAPI Spec](https://api.rateapi.dev/openapi.json) Skip to main content --- Source: https://rateapi.dev/api/reference Rate data API: https://api.rateapi.dev · OpenAPI: https://api.rateapi.dev/openapi.json · MCP: https://mcp.rateapi.dev/mcp