I run EstimatorSuite.com — we review
construction estimating software for US contractors (HVAC, electrical,
plumbing, roofing, landscaping).
We just open-sourced our entire calculator suite: 42 construction
calculators under MIT license. React + TypeScript + Tailwind.
What's included:
• 36 material calculators (concrete volume, roofing squares,
drywall, paint, flooring, etc.)
• 6 trade estimators (HVAC load, electrical conduit fill,
plumbing pipe sizing)
Two entry points:
→ React components — drop into any project
→ Pure calculation functions — zero UI dependency, works in
Node.js, Vite, Next.js, anywhere
Why we built this:
Construction software is expensive. Contractors told us they
needed free tools that actually work — not ad-filled spreadsheets.
So we built them, and we open-sourced them.
Top comments (1)
Nice split between React components and pure calculation functions — the zero-UI entry point is the part most people skip, and it's what makes these usable inside an existing estimating spreadsheet or a Node backend without rewriting the math. One suggestion from the estimating side: for anything with a waste factor or unit conversion (roofing squares, concrete volume), document the assumed waste percentage and rounding rule in the function docstring. Two contractors running the same calculator will otherwise get different bids and blame the tool. MIT license plus a live demo is a strong combo — thanks for open-sourcing these.