The five limbs of the day
Wherever you are, the sun and moon are sitting in a particular part of the sky right now, and the old calendar reads five simple things from exactly that. All of it is worked out live from their real positions, so there is nothing to predict here and nothing you need to believe.
Tithi dial · the sun–moon angle
Nakshatra wheel · the sidereal moon
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The day’s five limbs for your place
The reckoning that governs today, computed for your location at sunrise, the moment a Hindu day begins.
Worked out for your place at today's sunrise, the moment a Hindu day begins. These elements shift through the day and differ by location, so for ritual timing confirm against a local Panchang.
What a Panchang actually is
Panchang means “five limbs”. They are the five quantities that describe a Hindu calendar day: the tithi, the vara (weekday), the nakshatra, the yoga and the karana. Each one is a precise angle in the sky. Once you can find the longitude of the sun and the moon, all five fall out of simple arithmetic.
Tithi · the lunar day
A tithi is the time it takes the moon to gain twelve degrees on the sun. There are thirty in a lunar month. The waxing half, from new moon to full, is the bright fortnight, Shukla paksha. The waning half is the dark fortnight, Krishna paksha. The dial above places the new moon at the top and the full moon at the bottom, and the moon marker sweeps the gap.
elongation = (moon_longitude - sun_longitude) mod 360 tithi = floor(elongation / 12) + 1 // 1 to 30 paksha = tithi ≤ 15 ? Shukla (waxing) : Krishna (waning)
Nakshatra · the lunar mansion
The sky is divided into twenty-seven nakshatras, each thirteen degrees and twenty minutes wide. The nakshatra is simply the one the moon sits in. This is measured against the fixed stars, the sidereal zodiac, so the moon’s tropical longitude is first corrected by the ayanamsa before the wheel above is read.
sidereal_moon = (moon_longitude - ayanamsa) mod 360 nakshatra = floor(sidereal_moon / 13.3333) + 1 // 1 to 27
Yoga and Karana
The yoga is read from the combined longitude of the sun and the moon, again in twenty-seven steps. The karana is half a tithi, so there are sixty across the lunar month, named in a fixed cycle of eleven.
yoga = floor(((sidereal_sun + sidereal_moon) mod 360) / 13.3333) + 1 // 1 to 27 karana = floor(elongation / 6) + 1 // 1 to 60
Ayanamsa · fixed stars versus the seasons
Western astronomy measures longitude from the equinox, which drifts slowly against the stars over twenty-six thousand years. The Hindu calendar measures from the stars themselves. The gap between the two is the ayanamsa. We use the Lahiri standard, the official Indian value, in its linear form, which is good to within an arcminute and far finer than a nakshatra boundary needs.
ayanamsa ≈ 23.85 + 0.013972 × (year - 2000) // degrees // about 24.22° through 2026
Where the day begins
A Hindu day begins at sunrise, where the Western day begins at midnight. The weekday and the day’s ruling tithi are both read at the moment the sun’s upper edge clears the horizon. We compute that with the standard sunrise equation, taking the sun’s centre at minus fifty minutes of arc to allow for refraction and the sun’s own width. It is good to about a minute. Pick a place and see today’s figures.
Verification
A method is only worth trusting if it reproduces dates that are already settled. The table below is computed live, in this page, at Adelaide sunrise, and checked against the published 2026 Panchang. If anything ever drifts, you will see it here rather than be told it is fine.
| Date | Established | Computed here | Result |
|---|
What we do not claim
The sunrise is geometric. It does not account for your altitude or hills on the horizon, so a real sunrise can differ by a minute or two.
The instantaneous readout above is for this exact moment. A calendar day takes the tithi running at sunrise at a reference longitude, which is why the day’s observance can fall on a different date from the live tithi at your screen.
A few festivals turn on a special time of day rather than sunrise, such as Krishna’s midnight birth at Janmashtami or the midday window at Ganesh Chaturthi. Those follow the published Panchang rather than this engine, so we never ship a wrong date.
For ritual precision, a local Panchang prepared for your exact place remains the right reference. This page is built for everyday understanding and for showing the working.
Sources
Solar and lunar positions come from the open astronomy-engine library, which implements the VSOP87 theory for the sun and an ELP2000-based series for the moon. The sidereal correction uses the Lahiri (Chitrapaksha) ayanamsa, the standard adopted by the Indian calendar reform. The sunrise calculation follows the widely used sunrise equation. No external service is called; the arithmetic runs entirely in your browser.