The Panchanga

Ask why Deepavali fell on 20 October in 2025 but falls on 8 November in 2026, and someone will say, “It follows the moon.” That is half the answer. The Hindu calendar follows the moon and the sun, and stitches them together with a few elegant rules. Once you see those rules, the moving dates stop being a mystery — and the almanac your grandmother consulted before every wedding becomes a page you can read yourself.

Five limbs

The Hindu almanac is called the pañcāṅga (Tamil pañcāṅkam, பஞ்சாங்கம்), “five limbs,” because for every day it gives five measures of time. Two you already know from any calendar — the day of the week and, in a sense, the date. Three are less familiar, because they track the moon’s path rather than the clock. Tap each limb:

• 1तिथिTithiThe lunar day: one-thirtieth of the moon’s cycle. A new tithi begins each time the moon moves another 12° ahead of the sun. Because the moon’s speed varies, a tithi lasts roughly 19 to 26 hours — so it rarely starts at midnight or sunrise.
• 2वारVāraThe weekday, sunrise to sunrise, each ruled by a heavenly body: Ravi (Sun), Soma (Moon), Maṅgala (Mars), Budha (Mercury), Guru (Jupiter), Śukra (Venus), Śani (Saturn). In Tamil: Ñāyiṟu, Tiṅkaḷ, Cevvāy, Putaṉ, Viyāḻaṉ, Veḷḷi, Caṉi.
• 3नक्षत्रNakṣatraThe lunar mansion: the sky is divided into 27 segments of 13°20′, named after star groups, and the nakṣatra is the one the moon is passing through. It is the “birth star” of horoscopes, and many Tamil festivals are set by it.
• 4योगYogaAn astronomical “yoking”: add the longitudes of the sun and moon, and divide the circle into 27 parts. The 27 yogas run from Viṣkambha to Vaidhṛti; a few, such as Vyatīpāta and Vaidhṛti, are avoided for new undertakings. Nothing to do with the yoga of the mat.
• 5करणKaraṇaHalf a tithi. Seven “movable” karaṇas repeat through the month and four “fixed” ones fall around the new moon — eleven names for sixty half-days. One movable karaṇa, Viṣṭi (also called Bhadrā), is avoided for auspicious acts; it matters for the timing of Holi’s bonfire.

Tap a limb to read about it. Together they answer one question: what is the quality of this moment?

The day itself runs from sunrise to sunrise, not midnight to midnight. And the rule that governs most of daily life is simple: the tithi in force at sunrise colours the whole day. A tithi that begins after one sunrise and ends before the next is “lost” (kṣaya) and never names a day; one that spans two sunrises names both. That is why panchāṅgams occasionally skip a number or repeat one.

A month of the moon

Thirty tithis make one lunar month, split into two fortnights (pakṣa). The bright half, śukla pakṣa, runs from the day after new moon to full moon (pūrṇimā); the dark half, kṛṣṇa pakṣa, from the day after full moon to new moon (amāvāsyā). The tithis are counted one to fifteen in each half — Pratipadā, Dvitīyā, Tṛtīyā … Ekādaśī (the eleventh, the fast day of Ekādaśī) … up to Pūrṇimā or Amāvāsyā.

So a festival is named like an address: month + fortnight + tithi. Rama Navami is Caitra śukla navamī, the ninth of the bright half of Caitra. Ganesh Chaturthi is Bhādrapada śukla caturthī. Deepavali’s Lakṣmī Pūjā falls on the amāvāsyā that ends Āśvina in the amānta reckoning — the same night is the amāvāsyā of Kārtika in the pūrṇimānta reckoning (both explained next).

The twelve lunar māsas take their names from the nakṣatra near which the full moon falls: Caitra (from Citrā), Vaiśākha, Jyeṣṭha, Āṣāḍha, Śrāvaṇa, Bhādrapada, Āśvina, Kārtika, Mārgaśīrṣa, Pauṣa, Māgha and Phālguna. The Gītā honours one of them: among the months, Krishna says, he is Mārgaśīrṣa —

— the month Tamils call Mārkaḻi, the cool dawn month of the Tiruppāvai, which we meet on the festival calendar.

When does the month end?

Here is the single most confusing fact about Hindu dates, and once you have it you will never be confused again. India has two ways of ending a lunar month:

A year of the sun

Alongside the lunar months runs a solar year. The sun passes through the twelve signs of the zodiac (rāśi), and the moment it enters a new sign is a saṅkrānti. The best known is Makara Saṅkrānti, the sun’s entry into Capricorn in mid-January, kept by Tamils as Pongal.

The Tamil calendar is solar at its base. Each month begins at a saṅkrānti, so its months stay pinned to the Western calendar, moving by at most a day:

• Cittirai (சித்திரை, mid-April) — Tamil New Year, Puthandu, on or about 14 April. Kerala’s Vishu, Punjab’s Vaisakhi and the Bengali and Odia new years fall on or near the same solar day. (Vishu is not the Malayalam new year, though: the Kollam year begins on 1 Ciṅṅam, in August–September.)
• then Vaikāci, Āṉi, Āṭi, Āvaṇi, Puraṭṭāci, Aippaci, Kārttikai and Mārkaḻi (mid-December);
• Tai (தை, mid-January) — begins with Pongal; then Māci and Paṅkuṉi.

Tamil festivals often combine a solar month with a nakṣatra: Thaipusam is the day of the Pūcam star in Tai; Kārttikai Dīpam, the Kṛttikā star in Kārttikai; Paṅkuṉi Uttiram, the Uttiram star in Paṅkuṉi; Vaikāci Vicākam, the Viśākhā star in Vaikāci. Since the moon reaches each star about once a month, these festivals wander only within their solar month — and because these stars tend to coincide with the full moon in their month, they are usually full-moon festivals too.

The extra month

Twelve lunar months come to about 354 days; the solar year is about 365. Left alone, lunar festivals would slide all the way round the seasons, as the Islamic calendar’s months do. The pañcāṅga prevents this with a thirteenth month:

• Year with an extra month≈ 384 days
  Thirteen lunar months — catching up with the sun.
• Solar year सौर≈ 365 days
  The sun’s round of the twelve rāśis; the seasons and the Tamil months follow it.
• Twelve lunar months चान्द्र≈ 354 days
  About eleven days short of the sun each year.

The rule is beautifully simple. Normally the sun enters a new sign once during each lunar month. Occasionally a whole lunar month passes with no saṅkrānti in it; that month is declared adhika māsa, the “extra month,” and the real month of the same name follows it. This happens about every two and a half to three years — roughly seven times in nineteen years. (The rarer opposite case, a “lost month” or kṣaya māsa, with two saṅkrāntis, is very rare: one fell in 1822–23, the last in 1963–64, and the next is expected around 2124.)

The most recent was an adhika Jyeṣṭha, from about 17 May to 15 June 2026. The extra month is also called mala-māsa, the “impure” month, because weddings, house-warmings and other new beginnings are avoided in it; devotional traditions renamed it Puruṣottama māsa, Vishnu’s own month, and fill it with prayer, reading and charity. Community practice How strictly the restrictions are kept varies from family to family.

Why the dates move

Put the pieces together and the moving festivals make sense:

• Lunar festivals (set by tithi) arrive about eleven days earlier each year — then jump about nineteen days later in a year after an extra month. Deepavali: 20 October 2025, then 8 November 2026 (after the adhika Jyeṣṭha), then 28–29 October 2027. Navaratri: 11 October 2026, then 30 September 2027.
• Solar festivals (set by saṅkrānti) barely move: Pongal on 14 or 15 January, Puthandu on 13 or 14 April.
• Star festivals (solar month + nakṣatra) move within their month: Thaipusam on 1 February 2026, 22 January 2027.
• Place matters. The sun rises over Kuala Lumpur about an hour and a half before it rises over Chennai, so a tithi that is in force at sunrise in one place may not yet be in force in the other. A panchāṅgam is calculated for a particular longitude, so dates can differ by a day between India, Malaysia and the Americas.
• Each festival has its own moment. Not every festival follows the sunrise rule. Maha Shivaratri needs the fourteenth tithi at midnight; Janmashtami looks for the eighth at midnight, ideally with the Rohiṇī star; Ganesh Chaturthi wants the fourth at midday; Holi’s bonfire needs the full moon in the evening, outside the Bhadrā karaṇa. Each rule is spelled out in medieval digests of dharma such as Kamalākara Bhaṭṭa’s Nirṇayasindhu.

There is one more source of difference, especially for Tamils. Traditional vākya almanacs compute positions with old verse-formulae handed down in South India; tirukkaṇita or dṛk almanacs use modern astronomical calculation. They usually agree, but not always, and a temple following one may keep a festival a day apart from a temple following the other. So when your temple and your phone disagree, both may be right by their own reckoning. Community practice In Malaysia, most families simply follow the date their own temple announces.

Reading a panchāṅgam

A printed Tamil panchāṅgam or wall calendar crowds a great deal into one small square. Here is how to read a typical day’s entry, step by step — tap through:

The example times are illustrative, not taken from a real day. Layouts differ between publishers.

A word of balance. The pañcāṅga grew out of jyotiṣa, one of the six Vedāṅgas — the earliest surviving text, the Vedāṅga Jyotiṣa attributed to Lagadha, exists to time the Vedic rituals correctly. Its astronomy, refined over two thousand years, is real and impressive. Its lists of lucky and unlucky hours are a different matter: they belong to the tradition’s astrological layer, which many devout Hindus follow closely and others, including many teachers, sit lightly to. Seeker’s synthesis You can read the almanac for its rhythm of moon and festival without making every decision by it.

Tradition and history

In the tradition’s own view, the calendar is part of the cosmic order (ṛta): the same rhythm of sun, moon and seasons that the Vedic poets praised, and the frame in which every saṅkalpa is spoken — “in this year, in this month, on this tithi…” (see Time & Cosmology). Historians add that the system developed in layers: a lunar-solar ritual calendar in the late Vedic period; the twelve signs of the zodiac adopted from Greek and Babylonian astronomy in the early centuries CE; and a great age of mathematical astronomy from Āryabhaṭa (5th century) and the Sūrya Siddhānta onward. India’s official national calendar since 1957, the Śaka calendar, was itself a reform intended to bring the many regional reckonings together.

Test your reading:

Questions people often ask

Key terms on this page

Sources & further reading

• Bhagavad Gītā 10.35 — any standard edition.
• Robert Sewell and Śaṅkara Bālakṛṣṇa Dīkshit, The Indian Calendar (London: Swan Sonnenschein, 1896) — the classic technical account, with conversion tables.
• S. K. Chatterjee, Indian Calendric System (Publications Division, Government of India, 1998).
• Kim Plofker, Mathematics in India (Princeton University Press, 2009) — on the history of Indian astronomy, from the Vedāṅga Jyotiṣa to the Siddhāntas.
• Calendar Reform Committee, Report of the Calendar Reform Committee (Government of India, 1955), chaired by Meghnad Saha.
• Dates on this page checked against Drik Panchang and other published panchāṅga listings (October 2026).