1. What does this tool do
This free online date converter converts dates between six calendar systems instantly—Gregorian, Vietnamese Lunar (âm lịch), Chinese Lunar (农历), Islamic (Hijri), Hebrew (Jewish), and Persian (Jalali). Use it to find when Tết, Lunar New Year, Ramadan, Jewish holidays, or Nowruz fall in Gregorian (or the other way). No sign-up, no upload; all conversion runs in your browser. Ideal for holidays, anniversaries, and cultural events.
2. How to use it
Quick start: Choose “From” and “To” calendars, enter day/month/year in the source calendar, then view the converted date. Use for Tết, Ramadan, Hebrew dates, or Nowruz.
- Choose calendars — Select "From calendar" (e.g. Gregorian) and "To calendar" (e.g. Vietnamese Lunar, Chinese Lunar, Hijri, Hebrew, or Jalali).
- Enter date — Enter day, month, and year in the source calendar. For Vietnamese Lunar or Chinese Lunar, tick "Leap month" if the date falls in an intercalary month.
- View result — The converted date appears below. For Vietnamese Lunar, localized month names are shown; for Chinese Lunar, the result includes the original Chinese text (e.g. 十五, 正, 二〇二六). For Hebrew, the month name (e.g. Cheshvan) may be shown.
- Copy — Use the copy button to copy the result.
3. How it works
The tool uses Gregorian as the pivot: From calendar → Gregorian → To calendar. Vietnamese Lunar and Chinese Lunar use a lunisolar algorithm with leap months. Hijri uses Umm al-Qura; Hebrew uses the Jewish lunisolar calendar; Jalali uses the Persian solar calendar (Borkowski algorithm). All computation runs in your browser. No data is sent to any server.
4. Use cases & examples
- Tết and Lunar New Year — Find the Gregorian date of Vietnamese New Year (lunar 1/1).
- Ramadan / Eid — Convert between Hijri and Gregorian for Islamic holidays.
- Jewish holidays — Convert Hebrew dates to Gregorian (or the other way).
- Nowruz — Jalali 1/1 is the Persian New Year (around 20–21 March Gregorian).
- Annals — Convert birthdates or historical events across calendars.
Examples
- Gregorian 20 March 2024 → Jalali 1/1/1403 (Nowruz).
- Hijri 1 Ramadan 1446 → Gregorian equivalent (date depends on year).
- Hebrew 15 Cheshvan 5784 → Gregorian equivalent.
5. Limitations & known constraints
- Vietnamese lunar — Listed separately from Chinese Lunar for clarity; same lunisolar system. Naming follows Vietnamese usage; leap months must be indicated when converting lunar → Gregorian.
- Chinese lunar — Listed separately for SEO and display; same lunisolar system as Vietnamese. Official Vietnamese and Chinese dates may rarely differ by one day.
- Hijri — Umm al-Qura; supported range is limited. Other Hijri variants may differ.
- Hebrew — Uses the algorithms in jewish-date (MIT); not independently verified.
- Jalali — Solar calendar; algorithm may diverge outside the typical supported range.
- Library dependency — Accuracy depends on the respective libraries; not independently verified by this project.