Date Test Data Generator

Runs in browser Test Data

Random or systematic dates including edge cases (29 Feb, 31 Dec, year 2038, epoch 0, far future) in ISO, US, EU, Hijri-friendly and custom formats. All generated values are synthetic TEST DATA ONLY and do not belong to real people.

TEST DATA ONLY — all generated names, contacts, identifiers and numbers are synthetic and do not belong to real people or accounts.
Privacy: This tool runs entirely in your browser. Your input never leaves your device.

What is an ISO 8601 timestamp, and how does it relate to Unix time?

ISO 8601 writes a moment as 2026-09-23T10:15:00+03:00 — largest unit first, with an explicit UTC offset or Z — so it sorts as text and is unambiguous across locales; RFC 3339 is the Internet profile APIs use. Unix time is the same moment as a count of seconds (or milliseconds in JavaScript) since 1970-01-01T00:00:00Z, with no time zone at all. Most date bugs are an offset applied twice or a local time stored as if it were UTC.

How to use Date Test Data Generator

  1. Set the date range and the number of random dates.
  2. Pick a format (or write a custom pattern such as DD/MM/YYYY HH:mm).
  3. Keep the edge cases on for boundary testing.
  4. Press Generate and export.

Date Test Data Generator features

  • Random dates between two bounds, optionally with time of day and chronological order
  • 22 edge cases: epoch, Y2038, leap days, non-leap centuries, Excel and Windows epochs, DST transitions, leap second, 0001 and 9999 limits
  • Formats: ISO date, ISO date-time, US, EU, Unix seconds/ms, RFC 2822, long, tabular Hijri and custom token patterns
  • Each row includes ISO, Unix, weekday, weekend flags (Sat–Sun and Fri–Sat), leap-year flag and Hijri equivalent
  • Seedable; JSON, CSV, SQL, XML, JSON Lines or table output

Date Test Data Generator example

Custom pattern with edge cases

Input:

From 2024-01-01 to 2024-12-31 · Format: Custom "DD MMM YYYY" · Edge cases: on · Output: CSV

Output:

index,value,iso,…,note
1,01 Jan 1970,1970-01-01T00:00:00.000Z,…,Unix epoch (0)
2,31 Dec 1969,1969-12-31T23:59:59.000Z,…,One second before the epoch (negative timestamp)
3,19 Jan 2038,2038-01-19T03:14:07.000Z,…,Max signed 32-bit Unix time (Y2038)
…
6,29 Feb 2024,2024-02-29T00:00:00.000Z,…,Leap day
…
23,22 Jun 2024,2024-06-22T00:00:00.000Z,…,

Frequently asked questions about Date Test Data Generator

Which edge cases are included?

Unix epoch and the second before it, Y2038 rollover, leap days (2000, 2024), non-leap 1900 and 2100, Excel and Windows epochs, Y2K, DST transitions, a leap-second boundary and the 0001/9999 year limits.

What formats can I output?

ISO date, ISO date-time, US and EU order, Unix seconds and milliseconds, RFC 2822, long form, tabular Hijri and a custom token pattern (YYYY, MM, DD, HH, mm, ss…).

How accurate is the Hijri date?

It uses the arithmetic (tabular) Islamic calendar, which matches the Umm al-Qura calendar on most days but can differ by one day around month boundaries.

Why are weekend flags given twice?

isWeekend covers Saturday–Sunday and isFriSatWeekend covers Friday–Saturday, the weekend used across most of the Gulf.

References