About

HowMuchDoIBuy offers free, simple calculators that help homeowners and DIYers estimate building and garden materials before they buy.

What we do

Each calculator turns your measurements into a shopping quantity: cubic yards of concrete, gallons of paint, boxes of tile, bags of mulch or sheets of drywall. Every page explains the formula and shows a worked example, so you can check the math yourself.

How the calculators work

All calculations run in your browser. We do not ask for an account, and the numbers you type are not sent to our server. Defaults such as bag yields, paint coverage and material densities are typical published values; you can change most of them to match the product you are buying.

Accuracy

The results are planning estimates. Real projects vary with surface condition, cutting waste, product brand and site conditions. Always check product labels, manufacturer instructions and your local building code, and consult a qualified professional for structural work.

Feedback

Found an error or want a new calculator? Get in touch. We review every message and correct mistakes promptly.