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The DOT compliance knowledge API

49 CFR, decoded — as an API.

Verified verbatim eCFR plus a proprietary FMCSA-compliance strategy corpus, in one fast JSON API. It powers every X3 product — and now you can build on it: compliance software, brokers, TMS, insurers, AI agents.

Verbatim eCFR · strategy corpus · one endpoint away
Live

Search the knowledge base.

This box calls the real API. Try brakes, hours of service, 393.9, hazmat placard.

GET /api/search● LIVE
What's inside

Two layers, never mixed.

Verbatim eCFR

Real, verified regulation text pulled from the official eCFR — the only thing you'd ever quote as law. Look it up by citation: /api/cfr?c=49 CFR 393.9. If a section isn't verified, the API says so instead of guessing.

Parts 107, 171–180, 382, 385–397 and growing.

Strategy corpus

A proprietary, X3-authored knowledge base of 65,000+ compliance plays — DataQ defenses, CSA BASIC strategy, hazmat, HOS, drug & alcohol, audit prep. Clearly labeled as guidance, never as law. This is the part you can't get anywhere else.

Search + retrieve by topic, CFR reference, or BASIC.

Why it's defensible: the regulation text is public, but the strategy corpus is ours — authored, structured, and maintained by X3. You're licensing knowledge that doesn't exist anywhere else, not reselling public government data.

API pricing

Build on it.

Metered by request. Verbatim eCFR is always included; the strategy corpus unlocks on paid plans.

Free
$0

1,000 req / mo

  • Verbatim eCFR lookup
  • Search (titles + snippets)
  • No card — just start calling
Read docs
Most popular
Starter
$99/mo

25,000 req / mo

  • Everything in Free
  • Full strategy-corpus access
  • Key + usage dashboard
Get Starter
Pro
$499/mo

250,000 req / mo

  • Everything in Starter
  • Higher rate limits
  • Priority support
Get Pro
Enterprise
Custom

Unlimited + SLA

  • Volume pricing
  • Bulk export / sync
  • Dedicated support
Contact us
Docs

Five minutes to your first call.

Base URL https://x3dotskills.com. Auth via the x-api-key header or ?key=. Light use works with no key.

GET /api/cfr?c=49 CFR 393.9

Verbatim eCFR section. Also accepts ?part=393§ion=9.

curl "https://x3dotskills.com/api/cfr?c=49%20CFR%20393.9" \
  -H "x-api-key: x3k_your_key"
GET /api/search?q=brakes&type=all&limit=15

Full-text search across verbatim eCFR + the strategy corpus. type = all | cfr | skills.

curl "https://x3dotskills.com/api/search?q=hours+of+service&type=cfr"
GET /api/skill?slug=...

A single strategy document (guidance, not law).

curl "https://x3dotskills.com/api/skill?slug=dataq-citation-format-0017" \
  -H "x-api-key: x3k_your_key"
GET /api/usage?key=x3k_...

Your plan, quota, and usage this period.

Check your usage

Verbatim CFR is served from verified eCFR. Strategy-corpus content is informational and AI-assisted — not legal advice. © 2026 X3 Fleet Safety LLC.