About the Random Date Generator
This random date generator picks dates at random between a start date and an end date you choose. Generate a single surprise date night, a random birthday for a fictional character, a list of spot-check dates for an audit, test data for a spreadsheet or database, or random appointment slots for a study. Every eligible day in the range has the same chance of being chosen, and both the start and end dates are included.
Options let you restrict picks to weekdays (Monday to Friday), add a random time inside a window such as 09:00–17:00, prevent the same date being picked twice, sort the results in calendar order and output them as ISO (2026-03-14), US (03/14/2026), day-first (14/03/2026) or long form (Saturday, March 14, 2026).
The tool also reports how many days are eligible and the chance that the same date would come up twice if repeats were allowed — the same maths as the famous birthday problem, where just 23 random birthdays give better than even odds of a match. Dates are calendar dates with no time zone; weekends are Saturday and Sunday, and public holidays are not excluded.
How to use the random date generator
- 1Enter the start and end dates of your range.
- 2Choose how many random dates you need.
- 3Switch on weekdays only, no repeats or a random time window if needed.
- 4Pick the date format and whether to sort the list.
- 5Copy the list, or change any input to generate a new set.
Formula and method
The tool counts the eligible days N in the inclusive range (all days, or only Monday–Friday), then draws a uniform random offset from the start date for each pick. Weekend draws are rejected and redrawn, and with “No repeated dates” on, any date already chosen is redrawn too, so every eligible day keeps exactly the same chance. Random times are uniform whole minutes inside your time window.
The repeat chance is the classic birthday problem: the probability that k independent picks from N equally likely days are all different is the product of (N − i) ÷ N for i = 0 … k − 1, and one minus that is the chance of at least one shared date.
- N
- Number of eligible days in the range
- k
- Number of dates requested
Worked examples
Five random dates in 2026
All 365 days of 2026 are eligible. Five unique dates are drawn; had repeats been allowed, the chance of two landing on the same day would be 1 − (365 × 364 × 363 × 362 × 361) ÷ 365⁵ ≈ 2.71%.
Ten random weekday audit dates in Q3
July to September 2026 spans 92 calendar days, of which 66 are Monday–Friday. Ten unique weekdays are picked for spot checks. If repeats were allowed, ten picks from 66 days would collide about 51% of the time — which is why the no-repeat option matters.
23 random birthdays: the birthday paradox
With repeats allowed, 23 random dates from a 365-day year share at least one day 50.73% of the time. Run it a few times and you will see a duplicate in roughly every other list.
Every day of February 2024 in random order
2024 is a leap year, so February has 29 days. Asking for 29 unique, unsorted dates returns every day of the month exactly once in a shuffled order.
Frequently asked questions
Does the random date generator include the start and end dates?+
Yes. The range is inclusive, so a range from 1 January to 31 December has 365 eligible days in a common year and 366 in a leap year, and both end dates can be picked.
How do I generate a random birthday?+
Set the start and end dates to cover the birth years you want (for example 1980-01-01 to 2000-12-31) and generate one date. Each day in that span is equally likely, including 29 February in leap years.
Can I pick random weekdays only?+
Yes. Turn on “Weekdays only” and Saturdays and Sundays are skipped. Public holidays vary by country and are not removed, so delete any that fall on a holiday or regenerate.
How do I get a random date and time?+
Switch on “Add a random time” and set the earliest and latest times, such as 09:00 and 17:00. Each date gets a random minute inside that window, inclusive of both ends.
What is the birthday paradox?+
It is the surprising fact that among just 23 random people, the chance that two share a birthday is about 50.7%, and with 70 people it is over 99.9%. The repeat-chance output applies the same maths to your range.
Can I reproduce the same random dates later?+
Yes. Type any word or number as the seed. The same seed with the same range and options always returns the same list, which is useful for documented audit samples or repeatable test data.