Quick Answer: Tithi (तिथि) is the Vedic lunar day — the period during which the Moon-Sun angular distance increases by exactly 12°. There are 30 Tithis in a lunar month: 15 in the bright fortnight (Shukla Paksha, Moon waxing) and 15 in the dark fortnight (Krishna Paksha, Moon waning). Each Tithi has classical qualities (Nanda, Bhadra, Jaya, Rikta, Purna), a presiding deity, and specific activity affinities used in Muhurta selection.
What Is a Tithi?
The Sanskrit word तिथि (Tithi) means "lunar day." Unlike the solar day (sunrise to sunrise) used in modern civil life, the Tithi is the period during which the Moon-Sun angular distance increases by exactly 12° — one-thirtieth of the full 360° lunar cycle. The Tithi is the foundational unit of the Hindu lunar calendar.
Variable Duration
Because the Moon's orbital speed varies (faster near perigee, slower near apogee), Tithi durations are not constant. A typical Tithi lasts 19-26 hours. This means a solar day (24 hours) sometimes contains parts of two different Tithis. The Panchang lists which Tithi is "ruling" at sunrise — that becomes the day's primary Tithi for ritual purposes — and notes the time when the Tithi changes.
The Astronomical Definition
Tithi 1 (Pratipada) begins immediately after the new moon (Amavasya) when the Moon and Sun are at exactly 0° angular distance. As the Moon moves away from the Sun (ahead in zodiacal motion), the angular distance increases. Each 12° increase marks the boundary of a new Tithi. By Tithi 15 (Purnima, full moon), the Moon is exactly 180° from the Sun. Then Tithi 1 of Krishna Paksha begins, the Moon waning back toward 360° (which equals 0°, the next new moon).
Tithi vs Solar Day
The two timing systems coexist in Indian life. The civil calendar uses solar days (Monday, Tuesday, etc.). The ritual calendar uses Tithis. Festivals, fasts, and traditional ceremonies are scheduled by Tithi (Krishna Janmashtami on Krishna Paksha 8th of Bhadrapada, Diwali on Krishna Paksha 15th of Kartika, etc.). Solar weekdays still matter for Muhurta (Vara), but Tithis carry the deeper religious-ritual significance.
The Two Fortnights: Shukla and Krishna Paksha
The 30 Tithis of a lunar month are organised into two fortnights of 15 each.
Shukla Paksha (Bright Fortnight)
शुक्ल पक्ष (Shukla Paksha) is the bright fortnight — the period from new moon (Amavasya) to full moon (Purnima) during which the Moon's visible illumination increases. Tithis 1 through 15 of Shukla Paksha culminate in Purnima (full moon, the 15th Tithi of the bright fortnight).
Shukla Paksha is classically considered favourable for new beginnings, growth-oriented activities, celebrations, and any expansion-themed initiation. The waxing Moon's energetic signature supports building, creating, and adding to one's life.
Krishna Paksha (Dark Fortnight)
कृष्ण पक्ष (Krishna Paksha) is the dark fortnight — the period from full moon to new moon during which the Moon's illumination decreases. Tithis 1 through 15 of Krishna Paksha culminate in Amavasya (new moon, the 15th Tithi of the dark fortnight).
Krishna Paksha is classically favoured for introspection, ancestor-related rituals (especially around Pitru Paksha), purification practices, and "subtractive" activities — letting go, completing, releasing. The waning Moon's energetic signature supports inner work and dissolution.
Why the Distinction Matters
The same Tithi number — say, Tithi 5 (Panchami) — has different qualities depending on whether it falls in Shukla or Krishna Paksha. Shukla Panchami is bright, growth-oriented; Krishna Panchami is darker, more introspective. Festival dates often specify both: "Krishna Janmashtami" is Krishna Paksha 8th of Bhadrapada, distinct from Shukla Paksha 8th of Bhadrapada (which is its own minor observance).
Regional Calendar Conventions
Indian regions use different conventions for when a lunar month ends:
- Amanta (used in Maharashtra, Karnataka, Andhra, Tamil Nadu) — month ends on Amavasya (new moon). Krishna Paksha precedes the next month's Shukla Paksha.
- Purnimanta (used in North India and most other regions) — month ends on Purnima (full moon). Shukla Paksha precedes the next month's Krishna Paksha.
This means the "month" assigned to a given date can differ between regions even though the Tithi value is the same. For Muhurta purposes, this rarely matters; for festival timing, it occasionally does.
The Five Tithi Categories
Classical Vedic astrology classifies the 15 Tithis of a fortnight into five named groups, each with three Tithis. The same five categories repeat in both Shukla and Krishna Paksha.
The Five Groups
- Nanda (1st, 6th, 11th) — joyful, suitable for celebration, festivities, art, and creative beginnings.
- Bhadra (2nd, 7th, 12th) — auspicious, balanced, suitable for service activities, marriage Muhurta, and stable initiations.
- Jaya (3rd, 8th, 13th) — victorious, suitable for competitive activities, martial endeavours, court matters, and decisive action.
- Rikta (4th, 9th, 14th) — empty, classically inauspicious for new beginnings or auspicious activities. Suitable for elimination, harsh actions, or breaking patterns.
- Purna (5th, 10th, 15th) — complete, suitable for completion-oriented activities, religious ceremonies, and finalising projects.
Practical Implications
For most daily Muhurta purposes, the rough rule is: prefer Nanda, Bhadra, Jaya, and Purna Tithis; avoid Rikta Tithis for new auspicious activities. The 4th, 9th, and 14th of either fortnight are the most categorically avoided Tithis in classical Muhurta selection.
Exceptions
Some Rikta Tithis have specific positive associations that override their general inauspicious classification:
- Krishna Chaturdashi (14th) just before Amavasya is associated with Shiva worship and is auspicious for spiritual rituals.
- Maha Shivaratri falls on Krishna Chaturdashi of Phalguna and is universally observed despite being a Rikta Tithi — the Shiva association overrides the classification.
- The 4th Tithi (Chaturthi) of either fortnight is auspicious for Ganesha worship — Ganesh Chaturthi falls on Shukla Chaturthi of Bhadrapada.
The general principle: classical Tithi categories work for most activities, but specific deity associations create exceptions. Always check the day's deity-related festival markers in the Panchang before applying the general Tithi rules.
All 30 Tithis with Deities and Activities
Each of the 30 Tithis has a presiding deity and characteristic activities. The same numbered Tithi appears in both fortnights but carries the fortnight's broader quality (Shukla = bright/expansive; Krishna = dark/introspective).
Tithis 1-15: Detail Reference
| Tithi | Sanskrit Name | Deity | Category | Activity |
|---|---|---|---|---|
| 1 | Pratipada | Brahma (creator) | Nanda | Beginnings, foundation-laying, creative work |
| 2 | Dwitiya | Vidhata (ordainer) | Bhadra | Travel, business launch, agriculture |
| 3 | Tritiya | Vishnu (preserver) | Jaya | Education, decoration, jewellery, marriage |
| 4 | Chaturthi | Yama (death) / Ganesha | Rikta | Avoid new beginnings; auspicious for Ganesha worship |
| 5 | Panchami | Soma (Moon) | Purna | Healing, education, marriage, festival celebration |
| 6 | Shashthi | Kartikeya (war god) | Nanda | Conflict resolution, child-related rituals |
| 7 | Saptami | Surya (Sun) | Bhadra | Travel, ornamentation, royal activities, beginning of friendships |
| 8 | Ashtami | Shiva (destroyer) | Jaya | Conflict, destruction of obstacles, certain Shaiva rituals |
| 9 | Navami | Durga | Rikta | Avoid new ventures; auspicious for Durga worship |
| 10 | Dashami | Yama / Dharma | Purna | Religious ceremonies, dharmic activities, commitments |
| 11 | Ekadashi | Vishnu | Nanda | Fasting, spiritual practice, Vishnu worship |
| 12 | Dwadashi | Vishnu / Hari | Bhadra | Religious activities, breaking Ekadashi fast |
| 13 | Trayodashi | Kamadeva | Jaya | Marriage, marriage-related activities, auspicious initiations |
| 14 | Chaturdashi | Shiva / Kali | Rikta | Avoid new ventures; favoured for Shaiva and Shakta rituals (Maha Shivaratri) |
| 15 | Purnima / Amavasya | Moon (Shukla) / Pitris (Krishna) | Purna | Festivals on Purnima; ancestor rituals on Amavasya |
Special Tithi Observances
- Ekadashi (11th of either fortnight) — Vishnu worship and fasting day; one of the most universally observed Tithis among devotional Hindus.
- Pradosham — the period straddling sunset on the 13th Tithi, associated with Shiva worship.
- Sankashti Chaturthi — Krishna Chaturthi, especially in Bhadrapada, observed for Ganesha worship.
- Pitru Amavasya — the new moon (especially in Bhadrapada) for ancestor rituals.
- Purnima of various months — full moons of specific months mark major festivals (Holi, Guru Purnima, Sharad Purnima, Kartik Purnima, etc.).
Tithi Length Variability
Because Tithi durations vary, occasionally a single solar day spans almost an entire Tithi (when the Tithi is at its longest, ~26 hours, and the day starts just after a Tithi transition); other times a solar day contains parts of two Tithis (when the Tithi is short and the day spans a transition). The Panchang notes the running Tithi at sunrise plus the time of any Tithi change during the day. For ritual purposes, the Tithi at sunrise is typically used; for Muhurta selection of specific time windows, the actual Tithi at the chosen hour is used.
Tithi in Muhurta and Daily Life
Knowing the 30 Tithis is theoretical; using them in daily and Muhurta-related decisions is practical.
Tithi in Muhurta Selection
For any Muhurta selection, the day's Tithi is one of the five Panchang elements scanned. General Muhurta-favourable Tithis are 2nd, 3rd, 5th, 7th, 10th, 11th, 12th, and 13th. Avoid 4th, 6th (sometimes), 8th, 9th, 14th, 15th (Amavasya for new beginnings; Purnima is variable). Specific activities have their own Tithi preferences — wedding, business launch, housewarming all have classical Tithi recommendation lists. See our Muhurta complete guide for activity-specific Tithi selection.
Daily Tithi-Based Practice
Several traditional daily practices key off the running Tithi:
- Ekadashi fasting — observing partial or complete fast on Ekadashi (11th Tithi of either fortnight). Highly observed among Vaishnava devotees.
- Pradosham observance — visiting Shiva temples during the sunset window on the 13th Tithi.
- Sankashti Chaturthi — Ganesha worship on Krishna Paksha 4th, particularly observed by Ganesha devotees.
- Amavasya rituals — ancestor remembrance and tarpana on new moon days.
- Purnima observances — full moon days associated with specific deities depending on the month.
Festival Timing
Most Hindu festivals are timed by Tithi:
- Diwali — Krishna Paksha Amavasya of Kartika.
- Holi — Purnima of Phalguna.
- Krishna Janmashtami — Krishna Paksha 8th of Bhadrapada.
- Maha Shivaratri — Krishna Paksha 14th of Phalguna.
- Ganesh Chaturthi — Shukla Paksha 4th of Bhadrapada.
- Navratri — Shukla Paksha 1st through 9th of Ashvina.
- Raksha Bandhan — Purnima of Sravana.
Knowing the Tithi system helps you understand why specific festivals fall on specific dates and how the dates shift each Gregorian year (because the lunar calendar drifts relative to the solar calendar).
Personal Tithi Awareness
Some people observe the Tithi of their birth as personally significant. The day each lunar month when the Moon-Sun angle returns to the same Tithi as your birth is your "personal Tithi day" — sometimes used for personal spiritual practice or reflection. This is less commonly observed than personal Nakshatra days but exists in some traditions.
Modern Tithi Tools
Modern Panchang apps display the day's Tithi along with the four other Panchang elements. They also provide notifications for major Tithi-based observances (Ekadashi, Pradosham, festivals) so practitioners can plan around them in advance. The classical practice of consulting a printed annual Panchang has largely transitioned to mobile-app consultation, but the underlying Tithi system is unchanged. The Hindu calendar Wikipedia entry provides good additional reference for the broader calendrical system that contains the Tithi framework.
Frequently Asked Questions
- What is a Tithi?
- A Tithi is the Vedic lunar day — the period during which the Moon-Sun angular distance increases by exactly 12°. There are 30 Tithis in a lunar month: 15 in Shukla Paksha (bright fortnight) when the Moon waxes, and 15 in Krishna Paksha (dark fortnight) when the Moon wanes. Each Tithi has a presiding deity, classical quality, and specific activity affinities used in Muhurta selection.
- Why does Tithi duration vary?
- Because the Moon's orbital speed varies — faster near perigee (closest to Earth), slower near apogee (farthest from Earth). The Moon-Sun angular distance therefore increases at variable rates, making each Tithi (a fixed 12° increase) take a variable amount of time. Tithi durations range from approximately 19 to 26 hours, so a 24-hour solar day often contains parts of two different Tithis.
- Which Tithis are auspicious for new beginnings?
- The classical Muhurta-favourable Tithis are 2nd (Dwitiya), 3rd (Tritiya), 5th (Panchami), 7th (Saptami), 10th (Dashami), 11th (Ekadashi), 12th (Dwadashi), and 13th (Trayodashi) of either fortnight. Avoid 4th (Chaturthi), 8th (Ashtami), 9th (Navami), 14th (Chaturdashi), and 15th (Amavasya/Purnima for new auspicious activities, though they are favoured for specific deity rituals).
- What is the difference between Shukla Paksha and Krishna Paksha?
- Shukla Paksha is the bright fortnight from new moon to full moon — the Moon's visible illumination increases. Krishna Paksha is the dark fortnight from full moon to new moon — illumination decreases. Shukla Paksha is classically favoured for new beginnings and growth-oriented activities; Krishna Paksha is favoured for introspection, ancestor rituals, and "subtractive" activities like letting go or completing.
- How do festival dates relate to Tithi?
- Most Hindu festivals are timed by Tithi rather than by the Gregorian calendar. Diwali falls on Krishna Paksha Amavasya of Kartika; Holi on Purnima of Phalguna; Krishna Janmashtami on Krishna Paksha 8th of Bhadrapada; Maha Shivaratri on Krishna Paksha 14th of Phalguna. This is why festival dates shift each Gregorian year — the lunar calendar drifts relative to the solar calendar by ~11 days per year, with periodic leap month corrections.
Find Today's Tithi with Paramarsh
You now know the complete Tithi system — what a Tithi is, the two fortnights, the five categories, all 30 named Tithis with deities and activities, and how Tithi integrates with Muhurta and daily life. Paramarsh provides daily Tithi for your location alongside the day's Nakshatra, Yoga, Karana, and Vara — the complete Panchang at a glance.