A Nepali Age Calculator must use real Bikram Sambat month lengths. Adding 56 or 57 to a Gregorian year may provide rough context, but it cannot convert a complete date or calculate exact years, months, and days.
This tool accepts a Gregorian AD date or a Bikram Sambat date. It converts the birth date, calculates age in both systems, finds the next BS birthday, and limits calculations to a verified embedded table covering 1975–2099 BS.
Convert between Gregorian and Bikram Sambat birth dates and calculate exact BS and AD age within a documented table range. Bikram Sambat month lengths vary by year and cannot be reproduced accurately by merely adding 56 or 57 to the Gregorian year. This tool counts actual days against an embedded year-by-year month table for 1975–2099 BS. The verified table covers 1975 Baisakh 1 through 2099 Chaitra. Dates outside that range are rejected instead of approximated. Confirm conversions used for official Nepali documents with the relevant authority.Nepali Age Calculator
Bikram Sambat age
Why a lookup table is required
Supported range
Why Bikram Sambat Requires a Date Table
Bikram Sambat months do not follow one unchanging pattern in every year. Depending on the year and month, a month may contain 29, 30, 31, or 32 days.
That variation means a fixed year offset cannot identify the correct day and month. Accurate conversion requires the month lengths for each supported BS year and a known connection between one BS date and one Gregorian date.
The calculator uses 1975 Baisakh 1 = April 13, 1918 as its conversion epoch.
Formula and Table Method Used by the Nepali Age Calculator
To convert a BS date to Gregorian, the tool calculates a day offset:
Offset = completed BS-year days + completed month days + birth day − 1
That offset is added to the verified Gregorian epoch.
To convert Gregorian to BS:
- Calculate civil days since April 13, 1918.
- Subtract complete BS years using their stored month totals.
- Subtract complete months in the remaining BS year.
- The remaining value plus one becomes the BS day.
BS age then starts with:
Years = reference BS year − birth BS year
Months = reference BS month − birth BS month
Days = reference BS day − birth BS day
When days or months are negative, the tool borrows from the actual preceding BS month or year.
Choose AD or BS Input
Use Enter AD date when the birth date is recorded in the Gregorian calendar. The supported Gregorian range begins on April 13, 1918 and extends through the final day represented by the 2099 BS table.
Use Enter BS date when the Nepali date is known. Select the year, Baisakh through Chaitra, and the day. The tool checks the chosen year’s month length before accepting the date.
The calculation date is entered in Gregorian form because it provides a clear civil reference point for the comparison.
Details Provided in the Result
The main value is the completed Bikram Sambat age in years, months, and days. Supporting information includes:
- Birth date in BS
- Equivalent birth date in AD
- Calculation date in BS
- Gregorian chronological age
- Next BS birthday
- Gregorian equivalent of the next birthday
- Days until that birthday
- Any short-month adjustment
The comparison is useful because BS age components and Gregorian age components do not have to match even when both describe the same elapsed life.
Finding the Next BS Birthday
The calculator first tries the original BS month and day in the current BS year. If that date has already passed, it checks the next year.
If the original day does not exist in the target month, the birthday is placed on that month’s final valid day and the adjustment is disclosed.
Every target is calculated from the stored year-specific month pattern. It is not derived from the previous Gregorian birthday.
Supported Range and Validation
The embedded table covers 1975 Baisakh 1 through 2099 Chaitra. Dates outside this range are rejected because the tool cannot verify their month lengths.
This boundary is a quality feature. Extending the conversion with a guessed year offset could create convincing but incorrect dates.
The calculator has known cross-checks around the epoch and modern Nepali dates, but official documents should still be verified with the issuing authority or an official calendar.
For another calendar-aware age calculation with non-Gregorian month borrowing, see the Ethiopian Age Calculator.
Practical Uses for the Conversion
The Nepali Age Calculator is useful for birthday planning, filling parallel records, checking a date stated in BS against an AD calendar, and communicating dates between Nepal and countries that primarily use Gregorian dates.
It can also help families compare the birthday printed on different documents or determine the next Nepali-calendar anniversary without manually counting variable month lengths.
The result should not replace civil registration, passport, immigration, court, school, or financial records. Use it as a transparent planning and conversion tool, then confirm official uses with the relevant organization.
