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Date Connectivity

Accurately convert dates between the Bikram Sambat (BS) and Gregorian (AD) calendars. The Bikram Sambat year is approximately 56 years and 8.5 months ahead of the Gregorian calendar.

Nepali Date Converter (AD <-> BS)

Hello! Need to quickly change a Nepali date (Bikram Sambat – BS) to an English/Gregorian date (AD), or the other way around? Our free Nepali Date Converter makes it super simple — no sign-up, no fees, no complicated steps. Just type the date and get the result in seconds. This tool covers dates from around 1658 BS to 2100 BS (roughly 1601 AD to 2043+ AD), so whether it’s your birth date, passport expiry, visa application,School Birth date, old citizenship paper, marriage certificate, or historical record — it’s got you covered.

The Technical Proof

The Bikram Sambat (BS) is a solar calendar based on ancient Hindu traditions. Unlike the Gregorian calendar, the number of days in a BS month varies from year to year (ranging from 29 to 32 days) based on the sun's position in the zodiac.

To convert between AD and BS accurately, we use a reference epoch (Anchor Point):

$$ BS_{2000-01-01} \iff AD_{1943-04-13} $$

The conversion algorithm calculates the total integer days difference (\( \Delta D \)) from this anchor point. For AD to BS:

  • Calculate \( \Delta D \) between Input Date and 1943-04-13.
  • Iteratively subtract days for each BS year and month using a lookup table (since BS months are not algorithmic) until the remainder is less than the days in the current month.

Step-by-Step Logic

  1. Determine Direction: Identify if input is Gregorian (AD) or Bikram Sambat (BS).
  2. Calculate Total Days: Compute the exact number of days elapsed since the reference date (13 April 1943).
  3. Lookup & Accumulate:
    • If converting to BS: Start from BS 2000, subtract year-lengths from the total days until the remaining days fit within a single year. Then subtract month-lengths.
    • If converting to AD: Sum the days of all full BS years and months passed since the reference, then add this sum to the 1943-04-13 Gregorian date.
  4. Format Output: Construct the final YYYY-MM-DD string.

Nepali Date Converter | Convert BS to AD & AD to BS Online (Free & Accurate)

Why people love this converter

  • Lightning fast — results in 1–2 seconds
  • Very accurate — handles Adhik Maas (extra month), leap years, and all the tricky bits
  • Works both ways — BS to AD and AD to BS
  • Completely free and clean — zero annoying ads
  • Looks good on phone, tablet, or computer

How to Convert English Date to Nepali Date (AD to BS)

Enter the English/Gregorian date (example: 2025-01-30) Click “Convert to BS” You’ll instantly see the Bikram Sambat date (something like 2081-10-16 or whatever matches) Quick reminder: Bikram Sambat usually starts mid-April (around Baishakh 1), months have 29–32 days, and it runs about 56 years and 8–9 months ahead of the Gregorian calendar.