Century / Decade / Year Converter
Type any BCE or CE year and get its century, decade, millennium, regnal year, AD/BC equivalent — plus conversions to Hijri (AH), Vikram Samvat, Saka Era, Buddhist Era, Bengali Bangabda, Hebrew anno mundi and Roman Ab Urbe Condita (AUC). A famous-year lookup tells you what happened in that year.
What this tool does
Type a year, choose CE or BCE and the converter computes — instantly — the century (with the proper ordinal: 7th, 14th, 21st), the decade ("1940s CE"), the millennium ("3rd millennium CE"), the AD/BC equivalent and a continuous index across the era boundary. Optional accession + event-year inputs return the regnal year (12th of the king\'s reign). Below that, the tool shows seven non-Gregorian calendar conversions side by side, and a famous-year lookup tells you what milestone (if any) belongs to that year.
Calendar systems supported
- Common Era / BCE-CE — modern academic standard.
- Anno Domini / AD-BC — older Christian framing.
- Hijri (AH) — Islamic lunar calendar; Year 1 = 622 CE (Muhammad\'s migration to Medina).
- Vikram Samvat — Indian calendar; CE + 57.
- Saka Era — Indian National Calendar; CE − 78.
- Buddhist Era — Theravada Buddhism; CE + 543.
- Bengali Bangabda — Bangladesh and West Bengal calendar; CE − 593.
- Hebrew Era (anno mundi) — Jewish calendar; CE + 3760 (approx.).
- Roman Ab Urbe Condita (AUC) — "from the founding of the city"; CE + 753.
The conversions use linear formulas suitable for exam-style orientation. Lunar–solar drift in the Hijri / Hebrew / Buddhist calendars accumulates over centuries, so legal or religious use should rely on an astronomical converter.
The famous-year lookup
Type one of these years to see the famous-year card appear: 563 BCE (Buddha), 490 BCE (Marathon), 261 BCE (Kalinga War), 44 BCE (Caesar assassinated), 78 CE (Saka Era begins), 622 CE (Hijra), 732 (Tours), 1066 (Hastings), 1206 (Delhi Sultanate founded), 1453 (Fall of Constantinople), 1492 (Columbus), 1517 (Luther\'s Theses), 1526 (First Panipat), 1707 (Death of Aurangzeb), 1757 (Plassey), 1789 (French Revolution), 1857 (Indian Revolt), 1885 (INC founded), 1947 (Indian Independence), 1969 (Apollo 11) and many more.
The lookup carries about 70 milestone years in total — every major battle, dynasty, document or movement that an exam syllabus or general-history reader is likely to test.
BCE / CE and the no-year-zero rule
Modern academic chronology counts years backwards as BCE (Before Common Era) and forwards as CE (Common Era), with no year zero between them: 1 BCE → 1 CE. A figure born in 4 BCE who died in 33 CE lived 36 years, not 37 — there is no year zero to subtract. The tool computes spans correctly using a continuous internal index. If you type 0, the converter rejects it and explains why.
How to use the tool
- Type a Year.
- Pick CE or BCE.
- Optionally enter a Ruler accession year and an Event year to compute regnal year.
- Read the result card (century, decade, millennium, AD/BC) and the calendar conversions below it.
- If the year matches a famous milestone, the lookup card displays the event description.
- Use Copy CSV / Download JSON / Print from the action bar.
Worked examples
1947 CE → 20th century CE, 1940s CE, 2nd millennium CE, 1947 AD. Hijri ≈ AH 1366. Vikram = 2004. Saka = 1869. Buddhist Era = 2490. Roman AUC = 2700. The famous-year card highlights "Indian Independence and Partition".
1492 CE → 15th century CE, 1490s CE, 2nd millennium CE. Vikram = 1549. Saka = 1414. The famous-year card lists "Columbus reaches the Americas; fall of Granada; expulsion of Jews from Spain".
261 BCE → 3rd century BCE, 260s BCE, 1st millennium BCE. The famous-year card shows "Kalinga War — Ashoka converts to Buddhism".
FAQs
Which calendar systems are supported?
BCE-CE, AD-BC, Hijri (AH), Vikram Samvat, Saka Era, Buddhist Era, Bengali Bangabda, Hebrew anno mundi and Roman Ab Urbe Condita.
How accurate are the conversions?
Linear, exam-grade. Use an astronomical converter for legal or precise religious dates.
What is the famous-year lookup?
~70 milestone years from 563 BCE (Buddha) to 2008 CE (financial crisis).
How does the regnal-year helper work?
Enter accession and event year; the tool returns event − accession + 1.
Why is year zero rejected?
BCE-CE chronology has no year zero. Type a positive year and pick the era.