Hindu calendar


The Hindu calendar refers to a set of various lunisolar calendars that are traditionally used in the Indian subcontinent and South-east Asia, with further regional variations for social and Hindu religious purposes. They adopt a similar underlying concept for timekeeping based on sidereal year for solar cycle and adjustment of lunar cycles in every three years, however also differ in their relative emphasis to moon cycle or the sun cycle and the names of months and when they consider the New Year to start. Of the various regional calendars, the most studied and known Hindu calendars are the Shalivahana Shaka found in South India, Vikram Samvat found in Nepal, North and Central regions of India, Tamil calendar used in Tamil Nadu, and the Bengali calendar used in Bengal – all of which emphasize the lunar cycle. Their new year starts in spring. In contrast, in regions such as Kerala, the solar cycle is emphasized and this is called the Malayalam calendar, their new year starts in autumn, and these have origins in the second half of the 1st millennium CE. A Hindu calendar is sometimes referred to as Panchanga.
The ancient Hindu calendar conceptual design is also found in the Jewish calendar, but different from the Gregorian calendar. Unlike the Gregorian calendar which adds additional days to the lunar month to adjust for the mismatch between twelve lunar cycles and nearly 365 solar days, the Hindu calendar maintains the integrity of the lunar month, but insert an extra full month by complex rules, every few years, to ensure that the festivals and crop-related rituals fall in the appropriate season.
The Hindu calendars have been in use in the Indian subcontinent since Vedic times, and remain in use by the Hindus all over the world, particularly to set Hindu festival dates. Early Buddhist communities of India adopted the ancient Indian calendar, later Vikrami calendar and then local Buddhist calendars. Buddhist festivals continue to be scheduled according to a lunar system. The Buddhist calendar and the traditional lunisolar calendars of Cambodia, Laos, Myanmar, Sri Lanka and Thailand are also based on an older version of the Hindu calendar. Similarly, the ancient Jain traditions have followed the same lunisolar system as the Hindu calendar for festivals, texts and inscriptions. However, the Buddhist and Jain timekeeping systems have attempted to use the Buddha and the Mahavira's lifetimes as their reference points.
The Hindu calendar is also important to the practice of Hindu astrology and zodiac system.

Origins

The Vedic culture developed a sophisticated time keeping methodology and calendars for Vedic rituals, and timekeeping as well as the nature of solar and moon movements are mentioned in Vedic texts. For example, Kaushitaki Brahmana chapter 19.3 mentions the shift in the relative location of the sun towards north for 6 months, and south for 6 months.
Time keeping was important to Vedic rituals, and Jyotisha was the Vedic era field of tracking and predicting the movements of astronomical bodies in order to keep time, in order to fix the day and time of these rituals. This study was one of the six ancient Vedangas, or ancillary science connected with the Vedas – the scriptures of Vedic Sanatan Sanskriti.
David Pingree has proposed that the field of timekeeping in Jyotisha may have been "derived from Mesopotamia during the Achaemenid period", but Yukio Ohashi considers this proposal as "definitely wrong". Ohashi states that this Vedanga field developed from actual astronomical studies in ancient India. The texts of Vedic Jyotisha sciences were translated into the Chinese language in the 2nd and 3rd centuries CE, and the Rigvedic passages on astronomy are found in the works of Zhu Jiangyan and Zhi Qian. According to Subhash Kak, beginning of the Hindu calendar was much earlier. He cites Greek historians describing Maurya kings referring to a calendar which originated in 6676 BC known as Saptarsi calendar.
The Vikrami calendar is named after king Vikramaditya and starts in 57 BCE.

Texts

Dharmic scholars kept precise time by observing and calculating the cycles of i.e. the sun, moon and the planets. These calculations about the sun appear in various astronomical texts in Sanskrit, such as the 5th-century Aryabhatiya by Aryabhata, the 6th-century Romaka by Latadeva and Panca Siddhantika by Varahamihira, the 7th-century Khandakhadyaka by Brahmagupta and the 8th-century Sisyadhivrddida by Lalla. These texts present Surya and various planets and estimate the characteristics of the respective planetary motion. Other texts such as Surya Siddhanta dated to have been completed sometime between the 5th century and 10th century present their chapters on various deified planets with stories behind them.
The manuscripts of these texts exist in slightly different versions. They present Surya, planet-based calculations and Surya's relative motion to earth. These vary in their data, suggesting that the text were open and revised over their lives. For example, the 1st millennium CE Sanathana Dharma scholars calculated the sidereal length of a year as follows, from their astronomical studies, with slightly different results:
Hindu textEstimated length of the sidereal year
Surya Siddhanta365 days, 6 hours, 12 minutes, 36.56 seconds
Paulica Siddhanta365 days, 6 hours, 12 minutes, 36 seconds
Paracara Siddhanta365 days, 6 hours, 12 minutes, 31.50 seconds
Arya Siddhanta365 days, 6 hours, 12 minutes, 30.84 seconds
Laghu Arya Siddhanta365 days, 6 hours, 12 minutes, 30 seconds
Siddhanta Shiromani365 days, 6 hours, 12 minutes, 9 seconds

The Hindu texts used the lunar cycle for setting months and days, but the solar cycle to set the complete year. This system is similar to the Jewish and Babylonian ancient calendars, creating the same challenge of accounting for mismatch between the nearly 354 lunar days in twelve months, versus nearly 365 solar days in a year. They tracked the solar year by observing the entrance and departure of surya in the constellation formed by stars in the sky, which they divided into 12 intervals of 30 degrees each. Like other ancient human cultures, Hindus innovated a number of systems of which intercalary months became most used, that is adding another month every 32.5 months on average. As their calendar keeping and astronomical observations became more sophisticated, the Hindu calendar became more sophisticated with complex rules and greater accuracy.
According to Scott Montgomery, the siddhanta tradition at the foundation of Hindu calendars predate the Christian era, once had 18 texts of which only 5 have survived into the modern era. These texts provide specific information and formulae on motions of sun, moon and planets, to predict their future relative positions, equinoxes, rise and set, with corrections for prograde, retrograde motions, as well as parallax. These ancient scholars attempted to calculate their time to the accuracy of a truti. In their pursuit of accurate tracking of relative movements of celestial bodies for their calendar, they had computed the mean diameter of earth, which was very close to the actual 12,742 km.
Hindu calendars were refined during the Gupta era astronomy by Āryabhaṭa and Varāhamihira in the 5th to 6th century. These in turn were based in the astronomical tradition of Vedāṅga Jyotiṣa, which in the preceding centuries had been standardised in a number of works known as Sūrya Siddhānta. Regional diversification took place in the medieval period. The astronomical foundations were further developed in the medieval period, notably by Bhāskara II.

Astrology

Later, the term Jyotisha evolved to include Hindu astrology. The astrological application of the Hindu calendar was a field that likely developed in the centuries after the arrival of Greek astrology with Alexander the Great, because their zodiac signs are nearly identical.
The ancient Hindu texts on Jyotisha only discuss time keeping, and never mention astrology or prophecy. These ancient texts predominantly cover astronomy, but at a rudimentary level. Later medieval era texts such as the Yavana-jataka and the Siddhanta texts are more astrology-related.

Balinese Hindu calendar

Hinduism and Buddhism were the prominent religions of southeast Asia in the 1st millennium CE, prior to the Islamic conquest that started in the 14th century. The Hindus prevailed in Bali, Indonesia, and they have two types of Hindu calendar. One is a 210-day based Pawukon calendar which likely is a pre-Hindu system, and another is similar to lunisolar calendar system found in South India and it is called the Balinese saka calendar which uses Hindu methodology. The names of month and festivals of Balinese Hindus for the most part are different, though the significance and legends have some overlap.

Year: Samvat

Samvat refers to era of the several Hindu calendar systems in India and Nepal, in a manner that the consecutive years 1 BC and AD 1 mark the Christian era and the BC/AD system. There are several samvat found in historic Buddhist, Hindu and Jaina texts and epigraphy, of which three are most significant: Vikrama era, Old Shaka era and Shaka era of 78 AD.

Amanta and Purnimanta systems

Two traditions have been followed in the Indian subcontinent with respect to lunar months: Amanta tradition which ends the lunar month on no moon day, while Purnimanta tradition which ends it on full moon day.
Amavasyant tradition is followed by all Indian states that have a peninsular coastline, as well as Assam and Tripura.The states are Gujarat, Maharashtra, Karnataka, Kerala, Tamilnadu,Andhra pradesh, Telangana, and West Bengal. Odisha and all other states follow the Purnimanta tradition.
Purnimanta tradition was being followed in the Vedic era. It was replaced with Amanta system and in use as the Hindu calendar system prior to 1st century BCE, but the Purnimanta tradition was restarted in 57 BCE by Vikramaditya who wanted to return to the Vedic roots. The presence of this system is one of the factors considered in dating ancient manuscripts and epigraphical evidence of India that have survived into the modern era.

Paksha

A month contains two fortnights called pakṣa. One fortnight is the bright, waxing half where the moon size grows and it ends in the full moon. This is called "Gaura Paksha" or Shukla Paksha. The other half is the darkening, waning fortnight which ends in the new moon. This is called "Vadhya Paksha" or Krishna Paksha. The Hindu festivals typically are either on or the day after the full moon night or the darkest night, except for some associated with Krishna, Durga or Rama. The lunar months of the hot summer and the busy major cropping-related part of the monsoon season typically do not schedule major festivals.
A combination of the Paksha system, and the two traditions of Amanta and Purnimanta systems, has led to alternate ways of dating any festival or event in the historic Hindu, Buddhist or Jain literature, and contemporary regional literature or festival calendars. For example, the Hindu festival of colors called Holi falls on the first day of Chaitra lunar month's dark fortnight in the Purnimanta system, while the same exact day for Holi is expressed in Amanta system as the Purnima lunar day of Phalguna. Both time measuring and dating systems are equivalent ways of meaning the same thing, they continue to be in use in different regions, though the Purnimanta system is now typically assumed as implied in modern Indology literature if not specified.

Solar month names

There are 12 months in the Vedic lunar calendar. If the transits of the Sun through various constellations are used, then we get solar months, which do not shift with reference to the Gregorian calendar. In practice, solar months are mostly referred as Rāśi. The solar months along with the corresponding Hindu seasons and Gregorian months are:
RāśiVikrami
lunar months
Gregorian
months
Ṛtu
Ṛtu in Devanagari scriptBengali name for ṚtuGujarati name for ṚtuKannada name for ṚtuKashmiri name for ṚtuMalayalam name for ṚtuOdia name for ṚtuTamil name for ṚtuTelugu name for ṚtuTibetan name for ṚtuKalachakra tantra Tibetan-name for Ṛtu
VṛṣabhaJyeshthaMay–JuneGrīṣma
ग्रीष्मগ্রীষ্ম ગ્રીષ્મ ઋતુ ಗ್ರೀಷ್ಮ ಋತು گرٛێشِم
/greʃim/
ഗ്രീഷ്മം ଗ୍ରୀଷ୍ମ இளவேனில் గ్రీష్మ ఋతువు དཔྱིད་ཐ་མ་དང་དབྱར་ར་བ། སོ་ག
KarkaṭaShraavanaJuly-AugVarṣā
वर्षाবর্ষা વર્ષા ઋતુ ವರ್ಷ ಋತು ؤہراتھ
/wəhraːtʰ/
വര്‍ഷം‌ ବର୍ଷା முதுவேனில் వర్ష ఋతువు དབྱར་བར་མ་དང་དབྱར་ཐ་མ དབྱར་ག
KanyāAshvinSept-OctŚarad
शरद्শরৎશરદ ઋતુ ಶರದೃತು ہَرُد
/harud/
ശരത്‌ ଶରତ கார் శరదృతువు སྟོན་ར་བ་དང་སྟོན་བར་མ སྟོན་ཁ
Vṛścik‌‌‌aAgahana / MargashiraNov-DecHemanta
हेमन्तহেমন্ত હેમંત ઋતુ ಹೇಮಂತ ಋತು وَنٛدٕ
/wandɨ/
ഹേമന്തം‌ ହେମନ୍ତ குளிர் హేమంత ఋతువు སྟོན་ཐ་མ་དང་དགུན་ར་བ དགུན་སྟོད
MakaraMaghaJan-FebŚiśira
शिशिरশীত શિશિર ઋતુ ಶಿಶಿರ ಋತು شِشُر/ شِشِر
/ʃiʃur/ or /ʃiʃir/
ശിശിരം‌ ଶୀତ/ଶିଶିର முன்பனி శిశిర ఋతువు དགུན་བར་མ་དང་དགུན་ཐ་མ དགུན་སྨད
MīnaChaitraMar-AprVasanta
वसन्तবসন্ত વસંત ઋતુ ವಸಂತ ಋತು سونٛتھ
/sõ:tʰ/
വസന്തം‌ ବସନ୍ତ பின்பனி వసంత ఋతువు དཔྱིད་ར་བ་དང་དཔྱིད་བར་མ དཔྱིད་ཀ

Lunar months and approximate correspondence

The names of the Indian months vary by region. Despite the significant differences between Indo-European languages and Dravidian languages, those Hindu calendars which are based on lunar cycle are generally phonetic variants of each other, while the solar cycle are generally variants of each other too, suggesting that the time keeping knowledge travelled widely across the Indian subcontinent in ancient times.
The Tamil lunar month names are forward shifted by a month compared to Vikrami month names, in part because Tamil calendar integrates greater emphasis for the solar cycle in a manner similar to the neighboring Kerala region and it follows the Amanta system for lunar months. This is in contrast to Vikrami calendar which keeps the Purnimanta system and emphasizes the lunar cycle. A few major calendars are summarized below:
#Vikrami
Vikrami
AssameseBengaliKannada/TeluguKashmiriMalayalam
OdiaSindhiTamilTulu Tibetan Gregorian
1VaisākhaMēshaBöhagBoishakhVaisākha/wahʲakʰ/ or /beːsaːkʰ/MedamBaisakhaVaisakhu/ VihaauChithiraiPagguས་ག་ཟླ་བApril–May
2JyeshtaVrishaZethJjôisthôJyeshta/zeːʈʰ/EdavamJyesthaJethuVaigasiBēshaསྣྲོན་ཟླ་བMay–June
3ĀshādaMithunaAharAsharĀshāda/haːr/MithunamAsadhaAakhaar / AahaaruAaniKārtelཆུ་སྟོད་ཟླ་བJune–July
4ShraavanaKarkaXaünShrabônShrāvana/ʃraːwun/KarkadakamSrabanaSaanvanAadiAaṭiགྲོ་བཞིན་ཟླ་བJuly–August
5BhādraSingaBhadoBhādrô/BhāddurBhādrapada/bəːdɨr pʲatʰ/ or /bəːd rʲatʰ/ChingamBhadrabaBadro/ BaddoAavaniSonaཁྲིམས་སྟོད་ཟླ་བAugust–September
6AshwinaKanyaAhinAshshinĀswayuja/əːʃid/KanniAswinaAssuPurattasiKanya/Nirnālཐ་སྐར་ཟླ་བSeptember–October
7KartikaTulaKatiKattikKārtika/kaːrtikʰ/TulamKartikaKatiAippasiBontelསྨིན་དྲུག་ཟླ་བOctober–November
8Mārgasirsa
VrischikaAghünAgrohoyon/AghranMārgasira/mand͡ʒhor/ or /mɔnd͡ʒihoːr/VrischikamMargasiraNaahiri / MangharKarthigaiJārdeམགོ་ཟླ་བNovember–December
9PaushaDhanusPuhPoush/PūshPushya/poh/ or /pɔh/DhanuPousaPohuMargazhiPerardeརྒྱལ་ཟླ་བDecember–January
10MāghaMakaraMaghMaghMagha/maːg/MakaramMaghaManghuThaiPuyintelམཆུ་ཟླ་བJanuary–February
11PhālgunaKumbhaPhagunPhālgun/PhāgunPhalguna/pʰaːgun/KumbhamPhalgunaPhagunMaasiMāyiདབོ་ཟླ་བFebruary–March
12ChaitraMinaSótChoitrô_ChoițChaitra/t͡sitʰɨr/MinamChaitraChaituPanguniSuggiནག་པ་ཟླ་བMarch–April

Corrections between lunar and solar months

Twelve Hindu mas are equal to approximately 354 days, while the length of a sidereal year is about 365 days. This creates a difference of about eleven days, which is offset every = 2.71 years, or approximately every 32.5 months. The twelve months are subdivided into six lunar seasons timed with the agriculture cycles, blooming of natural flowers, fall of leaves, and weather. To account for the mismatch between lunar and solar calendar, the Hindu scholars adopted intercalary months, where a particular month just repeated. The choice of this month was not random, but timed to sync back the two calendars to the cycle of agriculture and nature.
The repetition of a month created the problem of scheduling festivals, weddings and other social events without repetition and confusion. This was resolved by declaring one month as Shudha and the other Mala or Adhika.
The Indian mathematicians who calculated the best way to adjust the two years, over long periods of a yuga, they determined that the best means to intercalate the months is to time the intercalary months on a 19-year cycle. This intercalation is generally adopted in the 3rd, 5th, 8th, 11th, 14th, 16th and 19th year of this cycle. Further, the complex rules rule out the repetition of Mārgasirsa, Pausha and Maagha lunar months. The historic Hindu texts are not consistent on these rules, with competing ideas flourishing in the Hindu culture.

Rare corrections

The Hindu calendar makes further rare adjustments, over a cycle of centuries, where a certain month is considered kshaya month. This occurs because of the complexity of the relative lunar, solar and earth movements. Underhill describes this part of Hindu calendar theory: "when the sun is in perigee, and a lunar month being at its longest, if the new moon immediately precedes a samkranti, then the first of the two lunar months is deleted." This, for example, happened in the year 1 BCE, when there was no new moon between Makara samkranti and Kumbha samkranti, and the month of Pausha was dropped.

Day

Just like months, the Hindu calendar has two measures of a day, one based on the lunar movement and the other on solar. The solar day or civil day, called divasa, has been what most Hindus traditionally use, is easy and empirical to observe, by poor and rich, with or without a clock, and it is defined as the period from one sunrise to another. The lunar day is called tithi, and this is based on complicated measures of lunar movement. A lunar day or tithi may, for example, begin in the middle of an afternoon and end next afternoon. Both these days do not directly correspond to a mathematical measure for a day such as equal 24 hours of a solar year, a fact that the Hindu calendar scholars knew, but the system of divasa was convenient for the general population. The tithi have been the basis for timing rituals and festivals, while divasa for everyday use. The Hindu calendars adjust the mismatch in divasa and tithi, using a methodology similar to the solar and lunar months.
A Tithi is technically defined in Indian texts, states John E. Cort, as "the time required by the combined motions of the sun and moon to increase or decrease their relative distance by twelve degrees of the zodiac. These motions are measured using a fixed map of celestial zodiac as reference, and given the elliptical orbits, a duration of a tithi varies between 21.5 and 26 hours, states Cort. However, in the Indian tradition, the general population's practice has been to treat a tithi as a solar day between one sunrise to next.
A lunar month has 30 tithi. The technical standard makes each tithi contain different number of hours, but helps the overall integrity of the calendar. Given the variation in the length of a solar day with seasons, and moon's relative movements, the start and end time for tithi varies over the seasons and over the years, and the tithi adjusted to sync with divasa periodically with intercalation.

Weekday/Vāsara

Vāsara refers to the weekdays in Sanskrit. Also referred to as Vara and used as a suffix. The correspondence between the names of the week in Hindu and other Indo-European calendars are exact. This alignment of names probably took place sometime during the 3rd century CE. The weekday of a Hindu calendar has been symmetrically divided into 60 ghatika, each ghatika is divided into 60 pala, each pala is subdivided into 60 vipala, and so on.
No.SanskritLatin weekdayCelestial objectAssameseBengaliBhojpuriGujaratiHindiKannadaKashmiriMalayalamMarathiNepaliOdiaPunjabi
RohingyaSylhetiTamilTeluguUrdu
1Ravivāsara
रविवासर or
Aditya vāsara
आदित्य वासर
Sunday/dies SolisRavi, Aditya = SunDêûbār/Rôbibār
দেওবাৰ/ৰবিবাৰ
Rôbibār
রবিবার
Aitwār
अतवार
Ravivār
રવિવાર
Ravivār
रविवार
Bhānuvāra
ಭಾನುವಾರ
/aːtʰwaːr/ Njaayar
ഞായർ
Ravivāra
रविवार
Aaitabar
आइतवार
Rôbibārô
ରବିବାର
Aitvār
ਐਤਵਾਰ
RooibarRôibbār
Nyayiru
ஞாயிறு
Ādivāraṁ
ఆదివారం
Itwaar
2Somavāsara
सोमवासर
Monday/dies LunaeSoma, Chandra = MoonXûmbār
সোমবাৰ
Śombār
সোমবার
Somār
सोमार
Sōmavār
સોમવાર
Somavār
सोमवार
Sōmavāra
ಸೋಮವಾರ
/t͡səndɨrwaːr/
Thinkal
തിങ്കൾ
Somavāra
सोमवार
Sombar
सोमवार
Somôbārô
ସୋମବାର
Somavār
ਸੋਮਵਾਰ
CómbarŚombār
Thingal
திங்கள்
Sōmavāraṁ
సోమవారం
ُPeer
3Maṅgalavāsara
मङ्गलवासर or
Bhaumavasara
भौम वासर
Tuesday/dies MartisMaṅgala = MarsMôṅôlbār/Môṅgôlbār
মঙলবাৰ/মঙ্গলবাৰ
Môṅgôlbār
মঙ্গলবার
Mangar
मंगर
Maṅgaḷavār
મંગળવાર
Maṅgalavār
मंगलवार
Maṁgaḷavāra
ಮಂಗಳವಾರ
/bomwaːr/
Chovva
ചൊവ്വ
Maṅgaḷavāra
मंगळवार
Mangalbar
मङ्गलवार
Môṅgôḷôbārô
ମଙ୍ଗଳବାର
Maṅgalavār
ਮੰਗਲਵਾਰ
MongolbarMôṅgôlbār
Chevvai
செவ்வாய்
Maṁgaḷavāraṁ
మంగళవారం
Mangal
4Budhavāsara
बुधवासर or
Saumya vasara
सौम्य वासर
Wednesday/dies MercuriiBudha = MercuryBudhbār
বুধবাৰ
Budhbār
বুধবার
Buddh
बुध
Budhavār
બુધવાર
Budhavāra
बुधवार
Budhavāra
ಬುಧವಾರ
/bɔdwaːr/
Budhan
ബുധൻ
Budhavāra
बुधवार
Budhabar
बुधवार
Budhôbārô
ବୁଧବାର
Buddhavār
ਬੁੱਧਵਾਰ
BuidbarBudbār
Budhan
புதன்
Budhavāraṁ
బుధవారం
Budh
5Guruvāsara
गुरुवासर
or
Brhaspati vāsara
बृहस्पतिवासर
Thursday/dies Iovis/JupiterDeva-Guru Bṛhaspati = JupiterBrihôspôtibār
বৃহস্পতিবাৰ
Brihôśpôtibār
বৃহস্পতিবার
Bi'phey
बियफे
Guruvār
ગુરુવાર
Guruvār
गुरुवार or
Brihaspativāra
बृहस्पतिवार
Guruvāra
ಗುರುವಾರ
/braswaːr/
Vyaazham
വ്യാഴം
Guruvāra
गुरुवार
Bihibar
बिहीवार
Gurubārô
ଗୁରୁବାର
Vīravār
ਵੀਰਵਾਰ
BicíbbarBirôiśôtbār
Vyazhan
வியாழன்
Guruvāraṁ, Br̥haspativāraṁ
గురువారం, బృహస్పతివారం, లక్ష్మీవారం
Jum'eraat
6Śukravāsara
शुक्रवासर
Friday/dies VenerisŚukra = VenusXukurbār/Xukrôbār
শুকুৰবাৰ/শুক্রবাৰ
Śukrôbār
শুক্রবার
Sukkar
सुक्कर
Śukravār
શુક્રવાર
Śukravār
शुक्रवार
Śukravāra
ಶುಕ್ರವಾರ
/ʃokurwaːr/
Velli
വെള്ളി
Śukravāra
शुक्रवार
Sukrabar
शुक्रवार
Śukrôbārô
ଶୁକ୍ରବାର
Śukkaravār
ਸ਼ੁੱਕਰਵਾਰ
CúkkurbarŚukkurbār
Velli
வெள்ளி
Śukravāraṁ
శుక్రవారం
Juma'a
7Śanivāsara
शनिवासर
Saturday/dies SaturnisŚani = SaturnXônibār
শনিবাৰ
Śônibār
শনিবার
Sanichchar
सनिच्चर
Śanivār
શનિવાર
Śanivār
शनिवार
Śanivāra
ಶನಿವಾರ
/baʈɨwaːr/
Shani
ശനി
Śanivāra
शनिवार
Sanibar
शनिवार
Śônibārô
ଶନିବାର
Śanīvār
ਸ਼ਨੀਵਾਰ
Chhanicchharavār
ਛਨਿੱਚਰਵਾਰ
CónibarŚônibār
Shani
சனி
Śanivāraṁ
శనివారం
Haftah

The term -vāsara is often realised as vāra or vaar in Sanskrit-derived and influenced languages. There are many variations of the names in the regional languages, mostly using alternate names of the celestial bodies involved.

Five limbs of time

The complete Indian calendars contain five angas or parts of information: lunar day, solar day, asterism, planetary joining and astronomical period. This structure gives the calendar the name Panchangam. The first two are discussed above.

Yoga

The Sanskrit word Yoga means "union, joining, attachment", but in astronomical context, this word means latitudinal and longitudinal information. The longitude of the sun and the longitude of the moon are added, and normalised to a value ranging between 0° to 360°. This sum is divided into 27 parts. Each part will now equal 800'. These parts are called the yogas. They are labelled:
  1. Viṣkambha
  2. Prīti
  3. Āyuśmān
  4. Saubhāgya
  5. Śobhana
  6. Atigaṇḍa
  7. Sukarma
  8. Dhrti
  9. Śūla
  10. Gaṇḍa
  11. Vṛddhi
  12. Dhruva
  13. Vyāghatā
  14. Harṣaṇa
  15. Vajra
  16. Siddhi
  17. Vyatipāta
  18. Variyas
  19. Parigha
  20. Śiva
  21. Siddha
  22. Sādhya
  23. Śubha
  24. Śukla
  25. Brahma
  26. Māhendra
  27. Vaidhṛti
Again, minor variations may exist. The yoga that is active during sunrise of a day is the prevailing yoga for the day.

Karaṇa

A karaṇa is half of a tithi. To be precise, a karaṇa is the time required for the angular distance between the sun and the moon to increase in steps of 6° starting from 0°.
Since the tithis are 30 in number, and since 1 tithi = 2 karaṇas, therefore one would logically expect there to be 60 karaṇas. But there are only 11 such karaṇas which fill up those slots to accommodate for those 30 tithis. There are actually 4 "fixed" karaṇas and 7 "repeating" karaṇas.
The 4
  1. Śakuni
  2. Catuṣpāda
  3. Nāga
  4. Kiṃstughna
The 7 "repeating" karaṇas are:
  1. Vava or Bava
  2. Valava or Bālava
  3. Kaulava
  4. Taitila or Taitula
  5. Gara or Garaja
  6. Vaṇija
  7. Viṣṭi
The Vedic day begins at sunrise. The karaṇa at sunrise of a particular day shall be the prevailing karaṇa for the whole day.

Nakshatra

are divisions of ecliptic, each 13° 20', starting from 0° Aries. The purnima of each month is synchronised with a nakshatra.

Festival calendar: solar and lunar dates

Many holidays in the Hindu, Buddhist and Jaina traditions are based on the lunar cycles in the lunisolar timekeeping with foundations in the Hindu calendar system. A few holidays, however, are based on the solar cycle, such as the Vaisakhi, Pongal and those associated with Sankranti. The dates of the lunar cycle based festivals vary significantly on the Gregorian calendar and at times by several weeks.The solar cycle based ancient Indian festivals almost always fall on the same Gregorian date every year and if they vary in an exceptional year, it is by one day.

Regional variants

The Indian Calendar Reform Committee, appointed in 1952, identified more than thirty well-developed calendars, in use across different parts of India.
Variants include the lunar emphasizing Vikrama, the Shalivahana calendars, as well as the solar emphasizing Tamil calendar and Malayalam calendar. The two calendars most widely used today are the Vikrama calendar, which is in followed in western and northern India as well as Nepal, and the Shalivahana Shaka calendar which is followed in the Deccan region of India.