# Tithi -- Meaning, Origin & How It's Used > A Tithi is a lunar day defined by the Moon moving 12° further from the Sun than it started, giving 30 tithis per lunar month rather than fixed 24-hour days. - **Canonical URL**: https://merirashi.com/en/glossary/tithi - **Language**: en --- 1. [Home](https://merirashi.com/en) 2. / 3. [Glossary](https://merirashi.com/en/glossary) 4. / 5. Tithi Glossary - Panchang & Muhurat ## Tithi Tithi Quick definition A Tithi is a lunar day defined by the Moon moving 12° further from the Sun than it started, giving 30 tithis per lunar month rather than fixed 24-hour days. Also known as: Lunar Day [Calculate your free birth chart](https://merirashi.com/en/birth-chart-calculator)[Browse the full glossary](https://merirashi.com/en/glossary) Definition ## What is Tithi? A tithi is the basic unit of the lunar calendar, defined not by clock time but by angle: one tithi is completed each time the Moon's longitude pulls 12° further ahead of the Sun's. Because the Moon's speed varies through its orbit, a tithi's actual duration varies too, ranging roughly between 19 and 26 hours rather than a fixed 24\. A lunar month contains exactly 30 tithis, split into two fortnights, or paksha: 15 waxing tithis, Shukla Paksha, from new moon to full moon, and 15 waning tithis, Krishna Paksha, from full moon back to new moon. Each tithi has its own name -- Pratipada, Dwitiya, Tritiya, and onward through Chaturdashi, ending each fortnight in Purnima, full moon, or Amavasya, new moon -- and its own classical associations governing which activities it favors or discourages. Tithi is one of the five limbs of the panchang and a foundational input for muhurat timing. Where the word comes from ## Etymology Tithi is Sanskrit तिथि, related to a root meaning to measure or apportion out -- fittingly, since the tithi apportions the lunar month into 30 measured angular segments rather than fixed clock hours. The concept predates modern astronomy and appears throughout classical Sanskrit astronomical and ritual literature as the basic reckoning unit for religious observances, fasts, and festival dating, which is why Hindu festival dates shift against the solar Gregorian calendar year to year -- they are fixed to a tithi, not to a fixed solar date. ## How it's used in a real chart A worked example, not just theory. Tithi governs which days are chosen for fasting, ritual, and major undertakings. Ekadashi, the eleventh tithi of each fortnight, is widely observed as a fasting day across Vaishnav and broader Hindu practice, considered spiritually purifying regardless of which paksha it falls in. Amavasya, the new moon tithi that closes Krishna Paksha, works the opposite way in practical planning: many practitioners avoid starting new ventures, moving into a new home, or beginning travel on Amavasya, since the moonless sky is classically read as inauspicious for fresh starts -- yet the very same tithi is the traditional day for Shraddha, ancestor-remembrance rites, since its theme of endings and the unseen realm suits honoring the deceased. A family planning a business launch will therefore check the panchang for the day's tithi, ruling out Amavasya and certain other tithis linked to obstacles, while a family observing a monthly ancestor ritual deliberately times it to Amavasya. This dual reading, same tithi, opposite guidance depending on the activity, is typical of how tithi analysis works throughout muhurat selection. No fear-selling ## Common misconceptions Myth vs. reality Because tithis are angle-based rather than clock-based, they do not line up neatly with calendar days the way a 24-hour day does. A tithi can begin mid-morning on one date and end mid-morning the next, meaning a single solar calendar date can contain parts of two different tithis, or, since a fast-moving Moon occasionally completes a 12° arc in under 24 hours, a short tithi can begin and end entirely within one sunrise-to-sunrise period, making the following calendar day appear to skip that tithi number entirely in some panchangs. Newcomers often assume this is a printing error or an inconsistency between sources; it is neither. It is the direct, expected consequence of measuring lunar days by angle instead of by clock, and any accurate panchang will show these same tithi overlaps and occasional skips for a given date and location. Go deeper ## Related tools & guides [See today's Panchang](https://merirashi.com/en/panchang) ## Frequently asked questions How many tithis are there in a lunar month? There are 30 tithis in a full lunar month: 15 waxing tithis making up Shukla Paksha, from new moon to full moon, and 15 waning tithis making up Krishna Paksha, from full moon back to new moon. Each has its own name and classical associations. Why do tithis not match up with regular 24-hour days? A tithi ends when the Moon has moved exactly 12° further from the Sun than it started, and the Moon's orbital speed varies, so a tithi's real duration ranges roughly between 19 and 26 hours rather than a fixed 24\. This is why tithi start and end times can fall mid-day. What is special about Ekadashi and Amavasya? Ekadashi, the eleventh tithi of each fortnight, is a widely observed fasting day across Hindu practice, considered spiritually purifying in both the waxing and waning half of the month. Amavasya, the new moon tithi, is traditionally avoided by many practitioners for starting new ventures, but is instead the customary day for Shraddha, the ritual remembrance of ancestors. Can a single calendar date have two different tithis? Yes. Because tithis are defined by lunar angle rather than clock time, a tithi can start or end at any hour, so one sunrise-to-sunrise calendar day can contain the tail of one tithi and the start of the next, or, less often, a tithi can begin and finish within a single calendar day. Explore ## Related terms [Panchang](https://merirashi.com/en/glossary/panchang) [Muhurat](https://merirashi.com/en/glossary/muhurat) [Choghadiya](https://merirashi.com/en/glossary/choghadiya) ## See Tithi in your own chart Definitions are a start. Compute your real birth chart to see exactly where this shows up for you -- free, in seconds. [Calculate my chart](https://merirashi.com/en/birth-chart-calculator)[Browse all terms](https://merirashi.com/en/glossary)