Holiday Entitlement Calculator

Somebody working three days a week, joining halfway through the year, on a 28-day policy, is entitled to 8.4 days. Rounded down that is 8, and a fifth of a day has just been taken off a part-timer by arithmetic nobody will ever look at.

This page rounds up. Only up. It shows the exact figure beside the rounded one so you can see what the rounding did, and it says on the page why it goes that direction: the errors in this calculation are small, they are repeated, and left to themselves they all fall on the same people.

It also shows the same policy at every working pattern, one to five days a week, so the pro-rata is a line you can check rather than a single answer you have to trust.

Every figure comes from the policy you type. This page does not know your country’s statutory minimum, your contract, your leave year or your carry-over rules, and it will not guess: one figure shipped to a worldwide audience would be wrong in most places and would look authoritative in all of them. It is arithmetic, not advice, and it cannot tell you whether what you typed is legal where you are.

Days and hours are handled as the different questions they are. Two part-timers can be owed the same number of days and very different amounts of time, if one works long days and the other short ones, and both figures are on the page.

It also catches the ordinary mistake: more days booked than exist. Better to find that in September than in December.

Save as many versions as you like and put any two side by side, figure against figure, with the better one on each line marked and the difference in its own column. That screen is the one that decides things, and it is the part a free calculator cannot do at all. Save one per person and the whole team is in the saved list.

One HTML file. No account, no subscription, no internet needed. Opens on Windows, Mac and Android; the readme explains the extra step on iPhone and iPad, where Apple blocks JavaScript in downloaded files and every tool of this kind is affected.

Everything lives in your browser on your device. Nothing is uploaded, which is why it works offline and why nobody else can see your figures — and it also means clearing your browsing data deletes it. The tool does not pretend otherwise: the header shows how long since your last export at all times, turns amber after three days and red after seven, and export is one click that produces a plain file you keep.