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This is an official ODERSA website. Here’s how you know

The official domain

The address of this site ends in odersa.org. Every service the association runs sits on a subdomain of odersa.org and nowhere else. If the address in your browser’s address bar does not end in odersa.org, this site is not ours.

Free, and no account

Everything is open straight away. No sign-up, no account, no password, no subscription, no advertising. Nothing is held back for those who pay, because there is nothing to pay for.

No data collected

This site does not follow you: no tracker, no tracking cookie, no measurement tool built into these pages, and nothing measured on your device. Our host counts requests in aggregate, as any server that answers does: a total, never a profile. You do not have to take our word for it: open your browser’s developer tools, go to the Network tab, and reload the page. You will see the full list of what the site asks for. Everything comes from odersa.org, nothing goes anywhere else.

Free to reuse

The content is published under the CC BY 4.0 licence. You may copy it, translate it, print it and pass it on, for your classes as much as for the people around you, on one condition only: credit ODERSA.

English
The WorkbenchTools that upload nothing
A workshop by the ODERSA associationNothing leaves, nothing is kept, nothing reaches us.

The workshop · The everyday corner

The everyday corner

Work out dates, gaps and deadlines

Every calculation is done at noon universal time, never at local midnight: at midnight a clock change shifts the date by a whole day, and that is the mistake that makes a deadline slip with no visible cause.

No input: this tool calculates

This tool asks for no file and no text: it CALCULATES, on your device. Pick the calculation and type your dates just below.

What this tool builds is never transmitted

The result is built inside your browser, on your device, and it is sent nowhere. Nobody but you ever sees it, and nothing is kept once the tab is closed. No server ever had to know it.

Checkable in ten seconds, without taking our word for it:

  1. Open your browser's inspector: the F12 key (or Ctrl+Shift+I, or Cmd+Option+I on a Mac).
  2. Go to the “Network” tab, then clear the list.
  3. Run the tool on this page, as many times as you like. The list stays empty: no request goes out.
  4. To go further: cut your connection, and do it again. The tool still builds.

This absence of requests is also checked BY MACHINE before every release: a lock drives a real browser, processes a real file, and refuses to publish if a single byte goes out.

The proof page, step by step and in pictures

Going further

InstructionsHow it works

This tool takes neither a file nor a text. Dates are typed as year-month-day, the international standard order, because it carries no ambiguity and sorts itself.

VerifyThe proof, step by step

The network inspector check, explained one gesture at a time, with screenshots.

The cornerThe everyday corner

The other tools in this corner of the workshop.

UnderstandHow this is built

The formats actually handled, browser by browser, and what we ruled out.