BuildCalc API

Vertical construction data API for AI agents and developers. 79 US-code-grounded calculators today, with codes, costs, products, and benchmarks verticals shipping as v1 ramps up.

Read the docs →

Quickstart, authentication, MCP integration, calculator reference.

Try a calc in 60s

Sign up, get an API key, call POST /v1/calc/concrete/yards.

What you get

  • 79 calculators across 16 categories (concrete, lumber, roofing, drywall, paint, flooring, HVAC, insulation, masonry, electrical, plumbing, doors-windows, gutters, stairs, site, misc).
  • US codes grounding. Every formula traces to IRC, IBC, NEC, IECC, IPC, ACI, IBC, TMS, DOE or a US manufacturer spec sheet (GAF, USG, TCNA, SW, etc.).
  • MCP server included. Point Claude Desktop, Cursor, or any MCP client at api.buildcalcapi.dev/mcp with a Bearer token and get 80 tools auto-discovered.
  • RFC 7807 errors + Idempotency-Key support + Stripe metered billing + GDPR-compliant export.

Coming next (v1 launch)

  • Codes vertical: ~500 most-cited sections from IRC, IBC, NEC, IECC, IPC + adoption matrix per US jurisdiction.
  • Costs vertical: metro-level material + labor indices from BLS PPI / OEWS + Census BPS.
  • Products vertical: ~6,000 SKUs across top 10 categories with manufacturer spec sheets indexed.
  • Benchmarks vertical: 15 project types with typical timelines + cost ranges, derived from Census + BLS + HUD data.