What Chakra is
Chakra is a calm, ad-free Hindu calendar and panchang. It comes as an app for iOS and Android, and as this website. The idea is simple: show you the tithi, the nakshatra, the festival dates and the daily timings you actually need, in a layout you can read at a glance, with nothing sold to you along the way. No banners, no pop-ups, no newsletter wall.
Correct for where you live
A tithi does not turn over at a national clock. It turns over at a moment in the sky, and the day it belongs to depends on when the Sun rises where you are. A festival that falls on Tuesday in Delhi can fall on Monday in San Francisco.
Chakra computes the panchang from your city's own latitude and longitude, so the tithi you see is the one running at your local sunrise. The website has daily panchang pages for 46 cities across India and the diaspora; the app covers 185 and lets you pin the one you live in.
How it's computed
The heavy astronomy runs once, when the site and app are built, using
astronomy-engine (an MIT-licensed library). That step produces plain tables of
transition times: when each tithi, nakshatra, yoga and karana begins and ends.
Sidereal positions use the Lahiri (Chitrapaksha) ayanamsa, the same reference
most widely followed Indian panchangs use.
At the time you open Chakra, it does very little: work out sunrise and sunset for your city, look up which anga was running at that moment, and apply the festival and vrat rules. No ephemeris ships in the app or the pages. This keeps everything fast, small and able to work offline.
Checked against Drik Panchang
The core promise is that the date is right. To keep ourselves honest, every build runs the festival and panchang output against a set of golden fixtures taken from drikpanchang.com. If a date drifts, the build fails. We would rather ship late than ship a wrong Ekadashi.
A short list of known one-day edge cases, and the classical tests behind them, is written out on the methodology page.
What it isn't
Chakra is a reference, not a ritual authority. It will tell you when a tithi begins and which day a vrat resolves to, but it does not choose your muhurat or settle a disputed observance for your family or sampradaya. For a specific wedding or griha pravesh muhurat, or when your local tradition differs from what you see here, ask your family priest or the panchang your community follows.
Made for the quietly devout
That line is the footer tagline, and it is the whole intent. Chakra is for people who keep vrats, mark festivals and check the tithi before starting something, and who would like a tool that does that job plainly. It is ad-free, carries no telemetry, and once loaded it works without a connection.