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
Los Angeles County (9,748,868 residents) sits within California, where dermatologists are listed at 6.36 per 100,000.
Three states whose dermatologist per-100k density is closest to California's — useful for benchmarking.
Plain-text citation block — paste verbatim into a brief, story, or report.
California has 2,508 active dermatologists (6.36 per 100,000 residents) — ranked 10 of 51 U.S. states + DC. Source: CMS NPPES NPI Registry + U.S. Census Bureau, snapshot 2026-05-06. Threshold for "underserved" in the parent study: 4 per 100,000. Citation: Fonteum Research, /research/dermatology-provider-supply-by-state-2026.