About the Thai Buddhist Calendar Converter
This Thai Buddhist calendar converter switches between Gregorian years (AD or CE) and the Buddhist Era (BE, พุทธศักราช or พ.ศ.) used officially in Thailand. Convert a single year in either direction, or enter a full date to see it written the Thai way — for example 29 กันยายน พ.ศ. 2569 — along with the weekday.
It is useful for reading Thai passports, visas, ID cards, work permits, contracts, receipts and product expiry dates, which almost always use BE years, and for filling in Thai government forms that expect a BE date of birth. Expats, travellers, HR teams and translators use it to avoid the common mistake of being off by 543 years — or by one.
Today the rule is simple: BE = CE + 543, with the year changing on 1 January. Before 1941, however, the Thai year began on 1 April, so dates in January to March of 1940 and earlier belong to the previous BE year (CE + 542). Date mode applies that historical rule automatically; the BE era was formally adopted in 1912, so earlier dates are shown retroactively.
How to use the thai buddhist calendar converter
- 1Choose year AD → BE, year BE → AD, or full date mode.
- 2Enter the Gregorian year, the Buddhist Era year, or a full date.
- 3Read the converted year, and the Thai-format date in date mode.
- 4For years before 1941, check the “BE year covers” line for the April-to-March span.
- 5Use the table of nearby years for quick look-ups.
Formula and method
The Thai solar calendar uses the same months, days and leap years as the Gregorian calendar; only the year number differs. Thailand counts years from the traditional date of the Buddha’s final passing (parinirvana), which puts the year 543 years ahead of the Common Era, so BE 2569 is AD 2026.
Thailand made the Buddhist Era official in 1912 with the year starting on 1 April. A 1940 decree moved New Year to 1 January from 1941, so BE 2483 lasted only nine months (1 April – 31 December 1940) and BE 2484 began on 1 January 1941. For dates from January to March before 1941 the converter therefore adds 542 rather than 543.
- BE
- Buddhist Era year (พุทธศักราช, พ.ศ.)
- CE
- Common Era / Anno Domini year (ค.ศ.)
Worked examples
What BE year is 2026?
Add 543 to 2026 and you get BE 2569. Since 1941 the Thai year has started on 1 January, so BE 2569 covers the whole of 2026.
Expiry date on a Thai label: 2570
A product marked หมดอายุ 2570 expires in 2570 − 543 = AD 2027.
A historical date: 15 February 1935
In 1935 the Thai year still began on 1 April, so 15 February 1935 was in BE 2477, which had started on 1 April 1934. That is 1935 + 542, not + 543. The day was a Friday.
Thai date for September 29, 2026
Modern dates simply add 543 to the year: Tuesday, 29 September 2026 is written 29 กันยายน พ.ศ. 2569 in Thai.
Frequently asked questions
How do I convert a Thai year to an English (AD) year?+
Subtract 543 from the Buddhist Era year. BE 2569 is AD 2026 and BE 2570 is AD 2027. To go the other way, add 543 to the AD year.
What year is it in Thailand?+
From 1 January to 31 December 2026 the Thai year is BE 2569 (พ.ศ. 2569). It becomes BE 2570 on 1 January 2027, because Thailand has started its year in January since 1941.
Why is the Thai calendar 543 years ahead?+
Thailand counts from the traditional date of the Buddha’s parinirvana. The resulting Buddhist Era is 543 years ahead of the Western Common Era. The months, days and leap years are otherwise identical to the Gregorian calendar.
Do other Buddhist countries use the same year?+
Not always. Cambodia, Laos, Myanmar and Sri Lanka also use Buddhist Era counts for religious purposes, but some place the epoch one year earlier, giving CE + 544, and their years often begin in April. This converter follows Thailand’s official civil calendar.
Why does my old Thai document seem to be off by one year?+
Before 1941 the Thai year began on 1 April. A document dated January, February or March of BE 2482, for example, is from 1940, not 1939. Use date mode, which applies that rule automatically.