Date calculator
Pick a start date, the direction and how many days, weeks, months or years to add or subtract. The result comes with the day of the week.
How to use this page
- Fill in the fields in the form above — the result recomputes at once, with no page reload.
- Under the result you will find the interpretation scale, if the calculator has one: it says which range your value fell into.
- The formula we use is shown lower on this page — you can check the arithmetic yourself.
- To compute the same for another game or variant, change it in the select field — prices and pools update automatically.
What this page does not do: It does not point to numbers to play and does not predict a draw — every draw is independent of the previous ones.
Further reading
Adding days to a date is unambiguous: 10 March plus 30 days is 9 April. Adding months and years is not, because months have 28 to 31 days. The calculator uses calendar semantics with clipping: it first adds years and months keeping the day number, and when that day does not exist in the target month it takes the month's last day. 31 January plus one month is 28 February, or 29 February in a leap year. Only then are weeks and days added.
The order matters. If days were added first and months later, 31 January plus one month and one day would give a different result from the everyday reading „in a month, and then one more day”. The chosen order matches how deadlines are counted in contracts and law: calendar units first, days last.
Leap years are handled automatically — a year divisible by 4 is a leap year unless it is divisible by 100 but not by 400. The year 2000 was a leap year, 2100 will not be. Dates from year 1 to 9999 are supported; a result outside that range ends with a message, not an invented date.
Frequently asked questions
What date is one month after 31 January?
28 February, or 29 February in a leap year. February has no 31st day, so the calculator takes the last day of the month.
Does the calculator handle leap years?
Yes. 29 February exists only in leap years, so 29 February 2024 plus one year is 28 February 2025.
In what order are the units added?
Years and months first (with day clipping), then weeks and days. That is how contract deadlines are counted.