Accurate, free online calculators for real-world projects.
LetsCalculator was built to solve a common frustration: needing a quick, accurate calculation for a real-world project — whether you're buying mulch for your garden, estimating concrete for a patio, or scaling a recipe for dinner guests. We believe everyone should have access to professional-grade calculators without needing a contractor's license or engineering degree.
We provide 50+ free online calculators across four categories:
Formulas verified against industry standards and manufacturer specs.
All calculations run in your browser. No data is sent to servers.
No sign-ups, no downloads. Just enter numbers and get answers.
Works perfectly on phones, tablets, and desktops.
Every calculator on LetsCalculator uses industry-standard formulas and is cross-referenced against manufacturer guidelines, building codes, and expert sources. Our construction calculators account for standard waste factors (typically 10-15% depending on material type), and all unit conversions follow NIST standards.
Found an error in a calculation? Have a suggestion for a new calculator? Reach out at [email protected]. We take accuracy seriously and will investigate any reported issues within 24 hours.