§ StatuteRates

The statutory interest rate API

Everything on this site is available as data — free, no key, no rate cards to scrape. Static JSON on a CDN, so it is fast to retrieve and has no application backend to maintain.

Endpoints

EndpointReturns
/api/v1/index.jsonService index — links + counts
/api/v1/meta.jsonDataset metadata, freshness, sources
/api/v1/entities.jsonAll series with current and latest-published values
/api/v1/latest.jsonFlat list of every current value (one call)
/api/v1/upcoming.jsonOfficially announced future periods, kept separate from current values
/api/v1/history-coverage.jsonCode-reviewed historical lookup series, date meanings, verified boundaries, and known gaps
/api/v1/entity/{slug}.jsonOne series — current, latest published, and full history with provenance
/api/v1/entity/{slug}.csvRecorded observations as CSV (spreadsheet-ready)

Every observation carries value, unit, effective_date, source_url, retrieved_at, confidence, method, and notes. Confidence describes the observation process; it does not make a state rule calculator-ready. A preannounced future period remains in latest_published and history, while current always means effective on the snapshot date.

Machine discovery

For AI agents (MCP)

An MCP server exposes the same dataset with tools for search, verified historical lookup (get_historical_value), comparison, and statutory-interest computation (calculate_interest) — so an agent can answer "how much interest has accrued on this judgment" with a citable, current figure instead of a stale guess. See the MCP setup guide for registration instructions. Historical lookup and state calculations use separate fail-closed release registries shared with the website; today, Florida is the only approved state-specific calculation method.

Fair use & licensing

Series directory

Dataset last compiled August 22, 2026. IRS quarterly; US Treasury/post-judgment weekly; UK statutory and EU Directive benchmark series semi-annual; BoE/ECB policy rates on decision. Refreshed weekly.