About CalcNest

CalcNest is a small, independent project with one goal: free calculators that show their work.

Why we show the formula

Most online calculators give you a number and nothing else. That's fine until the number looks wrong — then you're stuck. Every CalcNest tool publishes the exact formula it uses, the default assumptions (standard bag sizes, coverage per gallon, material densities, seeding rates), and notes on when those assumptions break down. You should never have to trust a black box for a home project.

How we keep it free

CalcNest is supported by unobtrusive display advertising. There are no accounts, no paywalls, no email harvesting, and no selling of data. The calculators run entirely in your browser — the numbers you type never leave your device.

Accuracy

Each calculator is built around published industry rules of thumb (for example, paint coverage of about 350 square feet per gallon, or mulch at 2–4 inches deep) and cross-checked against manufacturer guidance. Where real-world values vary — gravel density, wax blends, grass cultivars — we say so on the page and give you the assumption we used so you can adjust.

Suggestions welcome

Missing a calculator? Found a bug? Contact us — reader requests are prioritized.