Indian calendars

Adhik Maas Explained: The Hindu Intercalary Month that Keeps Seasons Aligned

How the lunar year of 354 days is synchronized with the solar year of 365 days via an extra month every 32.5 months.

By NaamSetu Editorial TeamPublished 6 September 20267 min read

A purely lunar year of 12 months contains roughly 354 days, while a solar year has roughly 365.24 days. Without correction, lunar festivals would drift across seasons by 11 days each year.

Check upcoming Adhik Maas occurrences on the [Hindu Calendar Guide](https://panchang.naamsetu.in/calendars).

## The Intercalary Mechanism To maintain seasonal alignment with solar equinoxes, the Hindu calendar inserts an extra month — **Adhik Maas** (also called Purushottam Maas) — approximately once every 32.5 months.

## Astronomical Determination An Adhik Maas occurs when a lunar month contains **no Surya Sankranti** (solar transit from one zodiac sign to another).

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