About

About ComponentCalc

Free, accurate material calculators built by someone who got tired of coming up short on the job.

ComponentCalc exists for one reason: estimating materials should be quick, accurate and free. Most material calculators bury the formula, default to one unit system, and leave you guessing how much extra to buy. We do the opposite.

What we do differently

  • Both units, everywhere. Every calculator and guide works in imperial and metric. Switch with one tap.
  • The formula is shown. You can see exactly how each number was reached, and check it.
  • We round up and add waste. Coming up short on a jobsite costs more than a little overage, so every estimate builds in a sensible waste factor.

The constants behind every tool, the bag yields, coverage rates and densities, are published in full on our methodology page.

A note on accuracy

These are planning estimates. Real materials vary, sites are rarely perfectly square, and supplier products differ. Always confirm your final quantity with the supplier before you buy. See our terms for the full disclaimer.

Knowledge Base

Estimating Guides & Reference

Plain-language guides on measuring, coverage and how much extra to buy, written for DIYers and trades.

Measuring & Estimating
Concrete & Aggregate
Soil & Lawn
Interior & Finishing