Privacy
The short version: fieldcalc is free to use, and like most free tools it pays its way through advertising and through anonymous data about which calculators get used. The measurements you type into a calculator are still worked in your browser and are not sent anywhere. Below, in plain language, is exactly what is collected and what you can do about it.
What runs on your device only
The arithmetic is local: the dimensions you type are calculated in your
browser and never transmitted. Whether you last used metric or imperial, and
a private tally of which calculators you open (so your most-used show first),
and the calculators you pin, hide or put in a list (fieldcalc.mytools),
are kept in your browser's local storage. Clearing your site data removes
them.
Imperial or metric
On your first visit we ask Cloudflare which country the request came from, only to pick imperial or metric for you. It isn't stored. Change it any time with the Imperial/Metric switch — your choice is kept in your own browser, and from then on we never ask again.
Sending results to yourself
"Email me" under a calculator sends the sheet — the numbers you typed, the answer and a link that reopens the calculator with them — as one email from fieldcalc, through our mail provider, to the address you type. We keep that address only if you tick the box to join the list; otherwise it is used for that one email and not stored. The send log keeps which calculator, when, and a salted hash of the address (the same hash counts sends toward a limit of five an hour) — not your numbers and not the address. If the address is already on file for an account or the list, the send is simply logged against it. Your browser remembers the address after a first send so it is there next time. Copy, Text it, Share and Print never leave your device.
"Email me" under a calculator sends the sheet — the numbers you typed, the answer and a link that reopens the calculator with them — as one email from fieldcalc, through our mail provider, to the address you type. The address is used for that one email and not stored. The send log keeps which calculator, when, and a salted hash of the address (the same hash counts sends toward a limit of five an hour) — not your numbers and not the address. If the address is already on file for an account, the send is simply logged against it. Your browser remembers the address after a first send so it is there next time. Copy, Text it, Share and Print never leave your device.
What the site records
So we can see which calculators are worth building more of — and so the site can earn its keep — fieldcalc records first-party usage data on its own servers: the pages you view, a coarse random visitor id kept in your browser (so return visits can be counted without knowing who you are), which site referred you, and — if you use the free app — that it was installed, saved for offline use, or opened (at most once a day). This is first-party — it goes to fieldcalc's own systems, not a third-party tracker following you around the web. It may be reported in aggregate or shared with partners as trends; it is not a public profile of you.
Reporting an error on a page stores your message, that page and the numbers you had entered — not your name, your email address or your IP address.
If you make an account
An account is optional and never required. If you sign in — with a one-tap email link, no password — we store your email and your synced preferences (units, most-used, pinned tools and lists) so they follow you between your devices. The sign-in link is sent through a transactional email provider on our behalf. Your email is used to sign you in and, if you opt in, for the occasional note when a new calculator goes up. Sign out or ask us to delete the account and it is gone.
If you add a work profile
Signed-in tradespeople can optionally leave a short "looking for work" profile — trade, location, contact details and a note. If you do, we store it so we can pass suitable work leads to you or reach out ourselves, and we may share it with employers looking to hire. Don't add one and none of that applies; ask and we'll delete it.
We don't run an email list at the moment. The only emails fieldcalc sends are the ones you ask for, when you ask: your results when you press Email me, and a sign-in link when you request one. If you were on the list before it closed, your entry is kept only so the one-click unsubscribe in any old email keeps working — ask and we'll delete it.
Newsletter
Every list box on the site is unticked; ticking it — in the footer, on the newsletter page, on your account, or under a calculator's results — is what puts your email on the list. We keep it on our own Cloudflare database with which site you signed up on, the page and form it was on, the date, the exact sentence beside the box, and the random visitor id your browser keeps. It is one list across our three sites — fieldcalc.net, bentright.com and sparkytools.net — so one unsubscribe takes you off all of them. A box ticked on a form is only a request until your inbox answers: we send one confirmation email, and nothing goes to the list until you tap the link in it (opening a sign-in link you asked for with the box ticked, or the switch on your account page, counts the same). Once you have unsubscribed, no form can put you back — only that confirmation or the switch can.
What we send: a short note at most every two weeks, and only when there is something related to the tools you use — the calculators you have opened or emailed yourself from, on any of the three sites, or new ones in the same drawers — from the site you signed up on. If we know nothing about what you use, the only note is what is new on that site. Every one carries a one-click unsubscribe and our mailing address, and none carries open or click tracking. The address is never sold or passed on as a list; a bounce or a complaint reported by our mail provider stops further sends.
Advertising
fieldcalc may carry advertising to stay free. Where an ad network is used it can set its own cookies and collect data under its own policy; where ads are sold directly they are a static image and a link with no third-party script. This page will always say which is in use.
Your choices
Clearing your browser's site data removes everything stored on your device, including the visitor id. You can unsubscribe from the newsletter in one click, sign out of an account at any time, and email hello@fieldcalc.net to have your account, work profile or newsletter entry deleted. A browser in private mode or with tracking protection on will limit what any of this can record.
Calculators that fit your work — by email, optional
Drop your email and tick the box: at most one short note every two weeks with calculators related to the ones you use — here and on bentright.com and sparkytools.net. One list across the three, one-click out, and nothing is sent until you confirm from your inbox.