About TheJobCalc
TheJobCalc is a small, independent set of estimating calculators for people doing their own home-improvement work.
Why it exists
Material estimating is simple arithmetic that is easy to get wrong under time pressure in a store aisle. Suppliers quote concrete in cubic yards, sell it in 80 lb bags, price tile by the box, and roofers talk in squares and bundles. Every one of those is a different unit for the same job. These calculators do the conversion in one step and round up the way a supplier invoices.
How the numbers are produced
Every result on this site comes from published geometry and standard package yields, all of which are shown on the calculator page itself — the formula, the constants used, and a worked example. Nothing is hidden behind the button. If a figure depends on a product-specific value, such as paint spread rate or bag volume, that value is an input you can change to match the label in front of you.
How the content is checked
Before any page goes live, an automated test suite re-runs every calculator against the worked example printed on its page — if the number you get from the form ever disagrees with the number in the text, the site does not deploy. Constants such as bag yields, coverage rates and framing spacings are taken from manufacturer labels and common US building practice, and the guides say so when a value varies by brand or by local code.
Every guide shows the date it was last updated, and the diagrams on this site are drawn specifically for it — they are not stock images.
Who runs it
TheJobCalc is independently built and maintained. It is not owned by, sponsored by, or affiliated with any material manufacturer or retailer, and no manufacturer sees or approves the content. When a reader reports an error (see below), the fix ships in the next deploy and the page's updated date changes.
What this site is not
It is not engineering advice. Slab thickness, reinforcement, footing depth, fastener schedules and ventilation requirements are governed by local building code and, for anything structural, by a licensed professional. Use these tools to buy the right amount of material, not to decide whether a design is sound. The same goes for the pay calculators: they are paycheck arithmetic from rates you supply, not tax advice — filing decisions belong with the IRS’s own tools or a tax professional.
Corrections and contact
If a formula, constant or conversion here looks wrong, tell us and it gets fixed — accuracy is the entire product. Email hello@thejobcalc.com.
How the site is funded
The calculators are free. The site is paid for by third-party display advertising, which is labelled and kept out of the calculator forms. Advertising does not influence the formulas or the material figures. See the privacy policy for how advertising cookies work.