Amanta vs Purnimanta: The Two Hindu Lunar Calendar Systems Explained

If you've ever noticed that the same Hindu festival is listed under different month names depending on whether you're consulting a North Indian or South Indian Panchang, you're witnessing the Amanta-Purnimanta difference in action. This isn't a discrepancy — it's two equally valid, scripturally recognized systems for measuring a lunar month.

What is a Hindu Lunar Month?

The Hindu calendar — known as Panchanga (पञ्चाङ्ग) — is a lunisolar calendar. Each lunar month is approximately 29.5 days long, measured from one phase of the moon to the next. What differs between the two systems is which lunar phase marks the end of the month.

Every lunar month has two fortnights (Pakshas):

Shukla Paksha (शुक्ल पक्ष): The bright fortnight — waxing moon (new moon → full moon).
Krishna Paksha (कृष्ण पक्ष): The dark fortnight — waning moon (full moon → new moon).

The question is: does the month end on the new moon (Amavasya) or the full moon (Purnima)?

The Amanta System (Amavasyant)

Amanta (अमान्त) — also called Amavasyant or Mukhyamana — is the lunar system where the month ends on Amavasya (the new moon day).

The month begins on Shukla Paksha Pratipada (the day after Amavasya).
Shukla Paksha comes first, followed by Krishna Paksha.
The month concludes on the next Amavasya.

Etymology: Ama (अमा) = new moon + Anta* (अन्त) = end. Hence, "ending with the new moon."

States that follow Amanta

Gujarat, Maharashtra, Goa, Karnataka, Andhra Pradesh, Telangana, and parts of Odisha. The Shalivahana Shaka calendar (established 78 CE), which is the basis of the Indian National Calendar, follows the Amanta system.

The Purnimanta System (Purnimant)

Purnimanta (पूर्णिमान्त) — also called Purnimant or Gaunitamana — is the lunar system where the month ends on Purnima (the full moon day).

The month begins on Krishna Paksha Pratipada (the day after Purnima).
Krishna Paksha comes first, followed by Shukla Paksha.
The month concludes on the next Purnima.

Etymology: Purnima (पूर्णिमा) = full moon + Anta* (अन्त) = end. Hence, "ending with the full moon."

States that follow Purnimanta

Bihar, Chhattisgarh, Haryana, Himachal Pradesh, Jammu & Kashmir, Jharkhand, Madhya Pradesh, Punjab, Rajasthan, Uttarakhand, and Uttar Pradesh. The Vikram Samvat calendar follows the Purnimanta system.

The Key Difference: Same Tithi, Different Month Name

This is the crucial point: both systems observe the same tithi (lunar day) on the same calendar date. The Shukla Paksha of any given month is identical in both systems. The difference arises in the Krishna Paksha — the same Krishna Paksha days carry a different month name.

How this works:

In the Amanta system, a month contains: Shukla Paksha → Krishna Paksha (both under the same month name).
In the Purnimanta system, a month contains: Krishna Paksha → Shukla Paksha (Krishna Paksha is named after the next* month compared to Amanta).

Practical Example: Maha Shivaratri

Maha Shivaratri falls on Krishna Paksha Chaturdashi (14th lunar day of the dark fortnight).

Amanta system: Magha Krishna Chaturdashi (because the Krishna Paksha of Magha is still part of Magha month).
Purnimanta system: Phalguna Krishna Chaturdashi (because in Purnimanta, this Krishna Paksha belongs to the next month, Phalguna).

Same day. Same tithi. Same festival. Different month label.

Another Example: Janmashtami

Krishna Janmashtami falls on Krishna Paksha Ashtami of Bhadrapada.

In Amanta: Shravan Krishna Ashtami.
In Purnimanta: Bhadrapada Krishna Ashtami.

Again — the actual date and tithi are identical. Only the month attribution differs.

Scriptural Basis

Surya Siddhanta

The Surya Siddhanta, one of the oldest and most authoritative astronomical texts in the Indian tradition, describes detailed methods for calculating lunar months, tithis, and the movements of the Sun and Moon. Both Amanta and Purnimanta reckonings are derived from the foundational mathematics laid out in this text.

Vedanga Jyotisha

The Vedanga Jyotisha — attributed to Sage Lagadha (c. 1400 BCE) — is the earliest known Indian text exclusively devoted to astronomical calculations. It is classified as a Vedanga (a limb of the Vedas) and establishes the basic structure of the lunisolar calendar, including the concept of the lunar month divided into two pakshas.

Arthashastra

Kautilya's Arthashastra references both the Amanta and Purnimanta reckonings in the context of revenue and administrative calendars, demonstrating that both systems were well-established and in parallel use during the Maurya period (4th century BCE).

Puranic References

The Vishnu Purana and the Brahma Vaivarta Purana describe the division of the month into Shukla and Krishna pakshas. The concept of Adhik Maas (intercalary month) — added every 32-33 months to synchronize the lunar year (~354 days) with the solar year (~365 days) — is also explained in Puranic literature and the Surya Siddhanta.

Why Two Systems Exist

Both systems are astronomically valid — they simply start counting the month from a different phase of the moon. Historically, different royal courts, regional traditions, and Siddhanta commentators adopted one system or the other.

The Shalivahana Shaka (South and West India) adopted the Amanta reckoning, while the Vikram Samvat (North India) adopted the Purnimanta reckoning. Over centuries, these became entrenched regional conventions.

Modern Indology literature typically defaults to the Purnimanta system when not otherwise specified, but both are equally authoritative.

Quick Comparison

Amanta (Amavasyant):

Month ends on: Amavasya (New Moon)
First fortnight: Shukla Paksha
Calendar era: Shalivahana Shaka (78 CE)
Regions: Gujarat, Maharashtra, Karnataka, Andhra Pradesh, Telangana, Goa
New Year: Chaitra Shukla Pratipada (Gudi Padwa / Ugadi)

Purnimanta (Purnimant):

Month ends on: Purnima (Full Moon)
First fortnight: Krishna Paksha
Calendar era: Vikram Samvat (57 BCE)
Regions: UP, MP, Bihar, Rajasthan, Punjab, Haryana, Himachal Pradesh, Uttarakhand
New Year: Chaitra Shukla Pratipada (same day as Amanta New Year)

How Muhuratam Handles This

On **Muhuratam*, all Panchang calculations are tithi-based and location-aware. Whether you follow the Amanta or Purnimanta convention, the tithi, nakshatra, yoga, and karana displayed for your city are astronomically accurate and identical in both systems.

Check the Panchang for your city to see today's complete Panchang data, including the exact tithi and paksha.

FAQ

Q: Do festivals fall on different days in the two systems?

A: No. The tithi (lunar day) of every festival is the same. Only the month name* may differ for festivals that fall in Krishna Paksha.

Q: Which system is more correct?

A: Neither — both are equally valid and scripturally recognized. They are two ways of labeling the same lunar cycle.

Q: Does this affect Muhurat calculations?

A: No. Muhurat timing is based on astronomical positions (tithi, nakshatra, yoga), which are independent of the Amanta/Purnimanta naming convention.

Q: I moved from Maharashtra to UP. Which system should I follow?

A: You can follow either — the underlying astronomy is the same. Most people adopt the convention of the region they reside in, but this is a matter of personal and family tradition.

Q: What about solar calendars in Tamil Nadu, Kerala, and Bengal?

A: These states primarily follow solar calendars (where month boundaries are determined by the Sun's transit through zodiac signs), not lunar month systems. The Amanta/Purnimanta distinction does not directly apply to solar calendars.

Explore accurate Panchang data for your city:

Check the Panchang to see today's tithi, nakshatra, yoga, karana, and more — accurate for any location in India and worldwide.

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