Nepali Date Converter: BS to AD and AD to BS

Pick a date on either calendar and it converts instantly. Covers Bikram Sambat 1978 to 2090, roughly 1921 to 2034 in the English calendar, which is enough for a birth certificate, a citizenship certificate, or anything else dated within a lifetime.

How the two calendars line up

Bikram Sambat is a lunar-adjusted calendar, so its 12 months don't line up with the Gregorian calendar the way, say, the Islamic calendar's fixed 354-day year does. Each BS month runs 29 to 32 days depending on the year, and a BS new year (Baisakh 1) usually falls in mid-April, but not on a fixed date. That's why converting between the two isn't a simple offset. It needs an actual reference table of how many days were in each month of each year, which is what this tool is built on.

Accuracy and supported range

This converter is accurate for BS 1978 through 2090, corresponding to English dates from April 13, 1921 onward. That covers essentially every birth date, citizenship date or historical record a Nepali citizen is likely to need. It stops at 2090 BS on purpose: Nepal's calendar committee only fixes month lengths a limited number of years ahead, and calendars further out than that aren't officially settled yet, so a tool that claims certainty past that point would be guessing.

Where you'll need this

• Filling out a form that asks for your date of birth in BS when your documents only show the AD date, or the reverse.
• Checking whether a citizenship certificate, passport or National ID date matches what's written on another document.
• Working out how many years, in BS, have passed since an event recorded in AD, or vice versa.