About fieldcalc

fieldcalc is a drawer full of small, sharp calculators for people who work with their hands — concrete and gravel, stairs and roofs, drywall and paint, lumber and landscape. One number, quickly, on whatever phone is in your pocket on the job.

What it is

Every tool does one thing and shows its working. Type your measurements and the answer updates as you go — there is no calculate button, no email gate, and no wall of ads over the input. Each page also spells out the assumption behind the number, because a takeoff you cannot check is a takeoff you cannot trust.

How it works

The whole site is static pages and a little arithmetic that runs in your browser. The measurements you type stay in the page — the maths never leaves your device — and your metric-or-imperial choice and the tools you reach for most are remembered locally so the next visit starts where you left off. That is why it loads fast and works on a weak signal.

It is free, and it stays free because it is supported by ads and by the usage it records: which tools get opened, from where, how often. There is an optional account (an email link, no password) for anyone who wants their preferences to follow them between phone and desk. What is kept and how to have it deleted is spelled out plainly on the privacy page.

Metric and imperial, always

A lot of the calculators out there are imperial-only, which is no use north of the border or across most of the world. Every tool here switches between the two, and remembers which you chose, so you are never converting in your head at the lumber yard. One switch at the top of every page sets it for the whole site — flip it and the numbers you have already typed convert with it, so a 16 ft room stays the same room at 4.88 m. On a first visit it starts in the system your country's trades use.

Keep the numbers

Under every result there is a "keep these results" row: Copy for the text to the yard, Text it on a phone, Share, a print-just-the-calculator button for the sheet for the truck — and Email me, which sends what you typed, the answer and a link that reopens the calculator with the same numbers in it, as one email from us through our mail provider. We keep the address only if you tick the box to hear about related calculators.

Still growing

There are more than eighty calculators now, in nine drawers — concrete & masonry, framing, site & landscape, finishes, measuring & layout, electrical, plumbing & HVAC, shop and conversions — and more go up most weeks. If you bend conduit for a living, that work has its own home at bentright — deeper than a broad index like this can go.

Found a number that looks off? The contact page has the address — a wrong result is the one thing worth interrupting us over.