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Panchanga

A free, offline-first Hindu calendar that runs entirely in your browser.

🌎 panchang.surendrajat.xyz

No accounts, no ads, no tracking. Install once, works offline.

Features

  • Panchanga — Tithi, Nakshatra, Yoga and Karana with end times, plus a sunrise-anchored Vara.
  • Calendar — lunar month (Masa) with Adhik Maas, Amanta/Purnimanta conventions, Vikram & Shaka Samvat, Ritu and Ayana.
  • Muhurtas — auspicious windows (Brahma, Abhijit, Vijaya, …) and inauspicious ones (Rahu Kaal, Yamaganda, Gulika).
  • Festivals — a pan-India set with rules aligned to Drik Panchang.
  • Sun & Moon — rise and set times, and the moon phase with illumination.
  • Kundli — Lagna, the nine grahas, bhavas, Vimshottari dasha, Navamsa, and Ashtakoota (guna milan) matching.
  • Sky & Learn — a live view of your local sky, and an interactive guide to how the panchanga is built.

Languages

English and हिन्दी, with Latin (1, 2, 3) or Devanagari (१, २, ३) numerals, and an optional transliteration toggle (Mesha/Maṅgala ↔ Aries/Mars).

Locations

Bundled cities cover India's metros and Hindu-diaspora centres worldwide, or use GPS — everything is computed locally for your true local sunrise.

How it works

Positions come from astronomy-engine (apparent geocentric, sub-arcsecond), sidereal with Lahiri by default (KP, Raman, Yukteshwar and True Chitra also available).

Panchanga elements match the Swiss Ephemeris exactly (anga indices identical, end times within ~40 seconds), and graha and Lagna positions agree to within ~0.5′; festival dates are verified against Drik Panchang. This is validated over 1925–2040, with festival rules covering 1950–2100 (matched to Drik Panchang for 2015–2028).

To learn the math and the why from scratch, read the guide; for terse references see METHODOLOGY, METHODOLOGY_JYOTISH and ARCHITECTURE.

Privacy

No server, no telemetry — everything lives in your browser. The service worker precaches the app so it loads instantly and works offline.

Run locally

pnpm install
pnpm dev      # http://localhost:5173
pnpm test     # unit + regression suite
pnpm build    # static output → ./dist

Requires Node 24 and pnpm 11 (both pinned).

Contributing

Bug reports, accuracy comparisons against local panchangas, and translations are welcome — see CONTRIBUTING.md.

License

Copyright 2026 @surendrajat · AGPL-3.0-or-later.

Contributors