This site does one thing: date and time arithmetic, with the convention it used written on the answer. It exists because most calculators give you a number and no way to tell whether they counted the start date, which holidays they skipped, or what they did with the end of a month — and those three questions are where two calculators disagree.
Who runs it
Datereckon is published by Prioton. The two names are deliberately separate: Datereckon is this site — the calculators, the prose and the answers — and Prioton is the independent publisher that builds and maintains it. Where an accountable party has to be named — an ad network's review, a copyright notice, a legal request — that party is Prioton.
It is a small operation. One person writes the prose, checks every published figure against the reference implementation before it ships, and reads the mail. That address is [email protected], and the contact page says what makes a report easy to act on.
How it is funded
Display advertising, and nothing else. There is no subscription, no paid tier, no affiliate link and no sponsored placement. No advertiser has any say over what a calculator returns — the answers are arithmetic, and there is nothing to sell in them. See the privacy policy for what the advertising does and does not collect.
How the answers are produced
Every calculation runs in your browser. Nothing you type into a calculator is sent anywhere; there is no server to send it to. The number shown when a page first loads was computed when the page was built — the site regenerates daily — and your browser recomputes it for your own date as soon as it loads. Both paths use the same rules, and a deploy whose answers do not match an independent reference implementation fails rather than shipping.
The full set of conventions is on the methodology page: how the start date is counted, how month ends clamp, which holidays we treat as non-working days, and which week-numbering system we quote.
Corrections
If a number here is wrong, please say so. A date calculator that is quietly wrong is worse than no calculator, and a specific report — the page, the inputs and the answer you expected — gets fixed faster than anything else we receive. The contact page has the route.
What this site is not
It is not legal, tax, immigration or financial advice. Statutory deadlines have their own counting conventions and their own holiday calendars, and a general-purpose calculator cannot know which apply to you. Use this to check arithmetic, not to decide a filing date. The terms of use say the same thing at more length.