From measurements to a shopping list in seconds
My DIY Calculator does the math so you don't have to. Here's exactly how we turn a few dimensions into the precise amount of material to buy.
Pick your project
Choose the calculator that matches what you're building.
We have 33+ calculators across concrete, landscaping, interior, decking, roofing and more — each built for a specific material and the way it's actually sold.
Enter your measurements
Type in your length, width, depth, or area.
Enter dimensions in the units you already have (feet and inches). The calculator handles the conversions — square feet to cubic yards, coverage rates, pack sizes — instantly as you type.
Buy the right amount
Get exact quantities in supplier units.
Your result comes back in the units stores sell: bags, sheets, boxes, rolls, cubic yards, and tons — with waste factored in where it matters, so you buy once and finish the job.
A worked example
Say you're pouring a concrete slab that's 10 ft × 10 ft, 4 inches thick.
You'd never want to eyeball that. Our concrete calculator does it instantly — and shows the answer in cubic yards and bags so you can order either way.
What makes the estimates accurate
Every calculator is built on the same real-world rules the pros use.
Industry coverage rates
Formulas use the standard coverage rates suppliers publish — like 350 sq ft per gallon of paint or 0.6 cu ft per 80 lb bag of concrete.
Built-in waste allowances
Materials that get cut or broken (tile, flooring, drywall) include a sensible waste percentage you can adjust for your layout.
Supplier-ready units
We round to whole sellable units so your result is a real shopping quantity, not a raw number you have to convert yourself.
Estimates are for planning — always confirm final quantities with your supplier, especially for large or structural jobs.