Literally meaning "side", a paksha is the period either side of the Full Moon Day (Purnima). A lunar month in the Hindu calendar has two fortnights, and begins with the New moon, (Amavasya). The lunar days are called tithis and each month has 30 tithis, which may vary from 20 – 27 hours. A paksha has 15 tithis, which are calculated by a 12 degree motion of the Moon. The first fortnight between New Moon Day and Full Moon Day is called "Gaura Paksha" or Shukla Paksha, the period of the brightening moon (waxing moon), and the second fortnight of the month is called Krishna Paksha, or "Vadhya Paksha", the period of the fading moon (waning moon). Nimach Panchang begin new lunar month from first day of Krishna Paksha while Gujarat Panchang begin new lunar month from first day of Shukla Paksha.
|Shukla Paksha||Krishna Paksha|
|1. Prathama||1. Prathama|
|2. Dwitiya||2. Dwitiya|
|3. Tritiya||3. Tritiya|
|4. Chaturthi||4. Chaturthi|
|5. Panchami||5. Panchami|
|6. Shashti||6. Shashti|
|7. Saptami||7. Saptami|
|8. Ashtami||8. Ashtami|
|9. Navami||9. Navami|
|10. Dashami||10. Dashami|
|11. Ekadashi||11. Ekadashi|
|12. Dwadashi||12. Dwadashi|
|13. Thrayodashi||13. Thrayodashi|
|14. Chaturdashi||14. Chaturdashi|
|15. Purnima||15. Amavasya, Ausi|
Shukla Paksha (Waxing Moon period) is a period of 15 days, which begins on the Shukla Amavasya (New Moon) day and culminating Purnima (Full Moon) day and is considered auspicious  because it is favorable to growth or expansion on every plane of existence i.e. Mental, Physical and Spiritual Plane.
|1st Day||Pratipada||Bali Pratipada, Govardhan Puja||Kartika|
|3rd Day||Tritiya||Akshaya Tritiya||Vaishakha|
|4th Day||Chaturthi||Ganesh Chaturthi||Bhadrapada|
|4th Day||Chaturthi||Ganesh Jayanti||Magha|
|5th Day||Panchami||Vivaha Panchami||Margashirsha|
|5th Day||Panchami||Basant Panchami||Magha|
|9th Day||Navami||Rama Navami||Chaitra|
|11th Day||Ekadasi||Shayani Ekadashi||Asadha|
|11th Day||Ekadashi||Vaikunta Ekadashi||Margashirsha|
|15th Day (Full Moon)||Poornima||Guru Purnima||Ashada|
Krishna paksha refers to the dark lunar fortnight or waning moon in the Hindu calendar. Krishna (Sanskrit: कृष्ण) is Sanskrit for "dark". Krishna Paksha is a period of 15 days, which begins on the (Full Moon) day (Purnima), culminating on (New Moon) day (Amavasya). Krishna Paksha is considered inauspicious, as the moon loses light during this period.
Festivals during Krishna Paksha are:
|4th Day||Chaturthi||Karva Chauth||Kartika|
|8th Day||Ashtami||Krishna Janmashtami||shravan|
|11th Day||Ekadasi||Vaikunta Ekadasi||Margashirsha|
|14th Day||Chaturdashi||Maha Shivaratri||Maagha|
|14th Day||Chaturdashi||Naraka Chaturdashi (Diwali)||Kartika|
In Vedic astrology when a person does a prasna (a question chart) and the planet Venus indicates the time period, the event referred to in the answer will happen in a pakṣa (fortnight) from the time the question was asked.
- Defouw, Hart; Robert Svoboda (2003). Light on Life: An Introduction to the Astrology of India. Lotus Press. p. 186. ISBN 0-940985-69-1.
- Kumar, Ashwini (2005). Vaastu: The Art And Science Of Living. Sterling Publishers Pvt. Ltd. p. 50. ISBN 81-207-2569-7.
- Monnier-Williams, M: (1851) Sanskrit Dictionary ISBN (none)
- Hindu calendar Archived 2010-09-01 at the Wayback Machine
- Moon Calendar
- Phases (Paksha) of the Moon from Rocking Baba
- "The Lunar Year".
- K. V. Sarma (2008), "Paksa", Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures (2nd edition) edited by Helaine Selin, Springer, ISBN 978-1-4020-4559-2.