Aathan Tamil Calendar 2027

Aathan Tamil Calendar — Panchangam, Rasi Palan, Muhurtham & Peyarchi, calculated with one documented method for every day from 1950 to 2100.

HOW AATHAN CALCULATES
Aathan uses the same set of calculations on every screen, so the daily calendar, muhurtham dates and horoscope screens always agree with each other.
• Planet positions are computed with the Swiss Ephemeris astronomy library, on the sidereal zodiac with Lahiri (Chitra-paksha) ayanamsa. This is the Thirukanitha method.
• Tamil month start dates follow the Vakya convention used in popular printed almanacs, so month dates match the panchangam you use at home.
• All timings are calculated for Chennai.
Vakya and Thirukanitha are both respected traditions. Aathan simply tells you which method each value comes from.

DAILY PANCHANGAM
• Thithi, Natchathiram, Yogam, Karanam — with exact start and end times
• Nalla Neram, Rahu Kalam, Yamagandam, Kuligai, Gowri Panchangam
• Amavasai, Pournami, Ekadasi, Pradosham, Sashti, Chaturthi, Ashtami, Navami
• Chandrashtamam and sun/moon nakshatra tracking
• Choose Madhyahna (midday) or Udaya (sunrise) tithi convention — your call

MUHURTHAM FINDER — THE RULES WE APPLY, LISTED OPENLY
Aathan selects muhurtham dates using these classical exclusion rules:
• Rikta tithi exclusion (Chaturthi/Navami/Chaturdashi)
• Guru Asta (Jupiter combustion), calculated from planetary positions
• Aadi and Margazhi masam exclusions
• Tuesday/Saturday exclusions (not applied to farming)
• Separate categories: Marriage, House-Warming, Business Opening, Vehicle Purchase, and Farming, each with its own rule set
• Valarpirai/Theipirai (waxing/waning) shown alongside every muhurtham date

RASI PALAN & PEYARCHI
• Daily, weekly, and monthly Rasi Palan for all 12 signs
• Guru Peyarchi and Sani Peyarchi (Jupiter & Saturn transit) tracking
• Transit predictions personalised to your birth star (all 27 nakshatras), not just your rasi

FESTIVALS, HOLIDAYS & FASTING
• Full Hindu festival and government holiday calendar
• Region-aware holidays for India, Sri Lanka, Singapore, Malaysia, UAE, USA, UK, Canada, Australia
• Fasting and vrat reminders (Ekadasi, Pradosham, and more)

WORKS OFFLINE
Full panchangam data is bundled on your device and syncs automatically when online — no waiting, no data charges to check tomorrow's tithi.

YOUR PRIVACY, RESPECTED
• No login or account required
• We never ask for your name, phone number or email
• Your notes and reminders stay on your device
• Full privacy policy available in-app and at techpuram.in/privacy-policy

Available in Tamil, English, and Tanglish (Tamil-in-English-script) — switch anytime in Settings.

Aathan Tamil Calendar — the Panchangam that shows its work.

Recent changes:
Enhanced the calculation for Santhirastramam.