About RoofTrussCalculator.com
RoofTrussCalculator.com is a free, independent web calculator built to help engineers, contractors, and homeowners size roof trusses and rafters quickly, without software installs, sign-ups, or paywalls.
Why We Built This
Roof truss math isn't complicated, but doing it by hand — or digging through a dozen different spreadsheets and PDFs — wastes time on every project. We built RoofTrussCalculator.com to put the standard span, pitch, load, and cost formulas that framers and engineers already use into a single, fast, free tool that works on any device.
The site grew out of a simple frustration: most calculators online are either locked behind a paywall, cluttered with intrusive ads, or too narrow to cover more than one roof type. We wanted one calculator that handles gable, hip, gambrel, mono, and steel trusses, plus dedicated tools for span, cost, load, and pitch — all free, all in one place.
What We Offer
- A live roof truss calculator covering 10+ roof and truss types, in imperial and metric units
- Dedicated calculators for span, cost, quantity, load, pitch, and rafter length
- A cost estimator with both automatic board-footage pricing and manual per-truss quote entry
- Free, in-depth guides on truss sizing, cost estimation, and load calculation
- No account, no download, and no cost to use any part of the site
Our Approach to Accuracy
Every formula on this site is built on standard, publicly documented structural engineering principles — the same rise-run-load relationships taught in framing and engineering references. We test the calculator's outputs against known worked examples to keep the numbers reliable for planning and estimating.
That said, RoofTrussCalculator.com is a planning and educational tool, not a substitute for a licensed structural engineer. Every result should be verified against your local building code and, for any permitted construction, reviewed and stamped by a qualified engineer before you build. See our full disclaimer for details.
Who This Site Is For
Framing contractors sizing a job before ordering material. Structural engineers and designers who want a fast sanity check before running full calculations. Homeowners and DIY builders trying to understand a quote or plan a small structure. Students learning how roof geometry and load calculations fit together. If you need a roof truss number in the next five minutes, this site is built for you.
Get in Touch
Questions, corrections, or feedback on the calculator? Visit our Contact page — we read every message.