Random Date Generator

Generate random dates within a custom year range and format.

From year

To year

Quantity

Format

How random dates are generated

Dates are generated by picking a random millisecond timestamp between the start of the "from" year (Jan 1 00:00:00 UTC) and the end of the "to" year (Dec 31 23:59:59 UTC), then formatting the result. Each date is fully independent — there is no deduplication, so you may occasionally see duplicates in larger sets.

For random times as well as dates, see the Unix Timestamp Converter.

Built and maintained by Meet Shah · Last updated 30 July 2026

What this tool is used for

Producing dates to populate a test fixture across a realistic range.
Generating input to exercise date parsing and formatting code.
Filling a mock dataset with plausible timestamps.
Creating boundary cases by narrowing the range to a month end or a leap year.
Producing sample data for a chart without using real records.

Frequently Asked Questions

Are dates drawn uniformly?: Uniformly across the DAY range, which is what you usually want. Note that uniform-by-day is not uniform-by-month, since months differ in length — February gets fewer draws than March, correctly.
Why do generated dates matter for testing?: Because date bugs cluster at boundaries: 29 February, month ends, year ends, and daylight-saving transitions. Random dates across a wide range hit these by accident in a way hand-picked test dates never do.
Which format should I output?: ISO 8601 (YYYY-MM-DD) for anything machine-read — it sorts lexicographically, is unambiguous, and is the only format where 03/04 cannot mean two different days. Localised formats are for display only.
Are timezones handled?: A date without a time has no timezone, and treating it as UTC midnight then displaying it locally is what shifts dates by a day. If your test data is date-only, keep it date-only through the whole pipeline.
Can I generate dates in the past or future only?: Yes, by setting the range — which matters because the two exercise different code. Past dates test age and history logic; future dates test expiry, scheduling and validation that rejects impossible values.
Which edge-case dates should test data include?: 29 February, the last day of a month, a daylight-saving transition, and 31 December in a non-UTC zone — where the date differs by one depending on where you stand. Those four find most date bugs.
Why is a range across an epoch boundary worth testing?: Because dates before 1970 are negative Unix timestamps, and code that assumes a positive value breaks on them. Birth dates routinely cross that line, which is where it usually surfaces.

Common errors and gotchas

Generating dates uniformly when real data is seasonal, which hides bugs a realistic distribution would find.
Overlooking the time zone, so a date near midnight lands on a different day for some readers.
Producing dates outside a system's valid range and reading the rejection as a tool problem.
Forgetting leap days, which a narrow range may never produce and which are a classic bug source.
Assuming the format is unambiguous, where day-month and month-day orderings differ.