I would like to see a calendar converter from Gregorian to Vikram Samvat (Kartak) a.k.a. Gujarati Vikram Samvat, where the new year starts on 01st Day of Kartak month. This calendar is widely followed by the prosperous Gujarati and Rajasthani communities.
This (Vikram Samvat Kartak) calendar functions exactly in the same manner as per the (present) Vikram Samvat Chaitra calendar you have on the system, but at only one difference...
A typical "Year" ends on Diwali festival which falls on Amavasya (Last day) of Asvina month (i.e., New Moon Day of Asvina Month) every year. New year starts of 1st Day of Kartika month.
Example of date conversion:
Gregorian Date Vikram Samvat (Chaitra) (i.e., Present) Vikram Samvat (Kartika)
24-Oct-2022 29-Asvina-2079 29-Asvina-2078 (Note the diff. in year)
26-Oct-2022 01-Karika-2079 01-Karika-2079 (Date diff is NOT there. Because 25-Oct-2022 was Diwali and from next day the year changed to 2079 -- as per Vikram Samvat Kartika calendar)
There is a very useful app called Calendar Magic available on http://www.woodcourt.co.uk/downloads.htm
In menu, go to Calendars > Calendars Comparison and select Hindu Lunisolar Kartika on one side and any other calendar on other side, to start comparing the dates
Please feel free to let me know in case you need more information.