Built on the authoritative federal record
The primary sources, named on every page.
These are the federal agencies whose public datasets Fonteum ingests and attributes — the issuing authorities, not customers or partners. Every figure on the site links back to one of them.
See the full source registry, with license and refresh cadence for each →
Reproducible by design
Every figure traces to its federal source.
14-tuple provenance
Every rendered fact ties to a source URL, dataset ID, snapshot date, row key, and SHA-256 — the full chain-of-custody record.
Reproducible SQL
Each study ships the exact query behind its figures, run against the cited federal snapshot. Re-run it yourself.
Daily reconciliation
Published counts are reconciled against the upstream federal datasets on a daily cadence, with drift logged.
Named medical review
Reviewed by Jennifer Montecillo, MD, medical reviewer. Non-practicing medical reviewer.
Two doors
Use the free API and open data
Query providers, facilities, sanctions, and quality scores — each field carrying its federal source. Self-serve, no call to start.
Talk to us
Managed pilots, enterprise terms, and audit-ready, signed attestation packages for compliance, risk, and research teams.
The substrate, by the numbers
Every fact Fonteum publishes traces to a specific government file with a known SHA-256. The chain below shows how: a claim records when the source asserted it (valid-time) and when we recorded it (system-time). Anyone can re-download the source file and confirm the hash — no login required.
valid_from, valid_to, and recorded_at columns (bitemporal).in-toto-witness/v1). The signed payload contains the SHA-256 of the snapshot contents.| Column | Axis | Meaning |
|---|---|---|
| valid_from | Valid-time start | When the source asserted this fact became true |
| valid_to | Valid-time end | When the fact stopped being true; null = still current |
| recorded_at | System-time | When Fonteum first wrote this row to the database |
Backfill note: valid_from ← asserted_at; recorded_at ← created_at. No valid-time was fabricated.
Paste a provenance_claims UUID to see its attestation chain.
The claim above has valid_from = 2026-06-10 and valid_to = null (current). When CMS releases updated data and a new claim supersedes this one, valid_to will be set and the diff will show the change.