About BuilderCal

BuilderCal is an independent collection of free planning calculators for construction, landscaping, and home-improvement projects.

Our Mission

Our goal is to make the first material estimate easier to understand and easier to verify. A calculator cannot inspect a jobsite, read a product label, or apply a local building code, so we show the assumptions behind each result and encourage users to confirm important orders with a supplier or qualified local professional.

Why Use Our Tools?

• Completely Free: No signups, no hidden fees, and no paywalls.
• Instant Results: Modern technology means your results calculate instantly as you type.
• Transparent Formulas: We show the formulas, default values, limitations, and reference material behind calculations so you can review the estimate yourself.
• Unit Switching: Seamlessly switch between imperial and metric units based on your preferences.

How the tools are maintained

Every calculator has a documented review date, unit conversions, editable assumptions where product values commonly vary, and a short list of limitations. Formula changes are checked against worked examples before publication. Supplier-specific coverage or density is not presented as a universal fact; when it matters, the input can be replaced with the number printed on the product data sheet.

Read the complete calculation methodology, editorial policy, and corrections process.

What BuilderCal is—and is not

BuilderCal is useful for early budgeting, comparing package sizes, and checking hand calculations. It is not an engineering service, a construction plan, or a substitute for permits, manufacturer instructions, code review, or a site inspection. Structural and safety-critical work should always be reviewed by an appropriately qualified professional.