About
Hi, I'm Vishwajeet.
I'm a 22-year-old software student, and I made Tithi Vidya because I couldn't find my own moon birthday.
Why I made this
My family told me about tithis
Not long ago, my family told me about tithis and the panchang. I learned that I have a second birthday, one that follows the moon.
I couldn't find mine
I wanted to know two things: the tithi I was born on, and the date my moon birthday falls on this year. I could not find a simple way to get either.
So I built it
So I made Tithi Vidya. Enter your birth date, time and place, and it shows your tithi and your moon birthdays for 100 years. Now no one has to face that problem again.
Who I am
I'm Vishwajeet Sharma. I'm 22, and I study software. The part I enjoy most is DevOps: building things, shipping them, and keeping them running smoothly.
Tithi Vidya is a small project built with a lot of care. The tithi engine is written in Rust and runs right in your browser, and the How it works page shows the real code and every test.
Why I want to share it
India has timed its festivals by the moon for over 2,000 years. I want the world to see how.
When my family told me about tithis, I was surprised by how clever the idea is. The calendar was worked out by watching the sky, written down by astronomers, and is still printed in panchangs found in millions of homes. It decides when Diwali, Holi and Navratri fall, and when your moon birthday comes round.
Yet most people outside India have never heard of it, and many of us who use it couldn't explain it. Tithi Vidya is my way of changing that: plain words, real astronomy, and a free tool anyone in the world can use.
Shukla paksha the moon grows
- Pratipada
- Dwitiya
- Tritiya
- Chaturthi
- Panchami
- Shashthi
- Saptami
- Ashtami
- Navami
- Dashami
- Ekadashi
- Dwadashi
- Trayodashi
- Chaturdashi
- Purnima
Krishna paksha the moon shrinks
- Pratipada
- Dwitiya
- Tritiya
- Chaturthi
- Panchami
- Shashthi
- Saptami
- Ashtami
- Navami
- Dashami
- Ekadashi
- Dwadashi
- Trayodashi
- Chaturdashi
- Amavasya
From the sky to your screen
Over 2,000 years ago
The Vedanga Jyotisha, one of India's oldest texts on time, explains how to follow the sun and moon to set the days of rituals.
499 CE
Aryabhata, aged 23, finishes the Aryabhatiya. His figures for the sun and moon guide Indian astronomers for centuries.
Today
Panchangs are printed every year in many languages. Hundreds of millions of people use them to choose days for festivals, fasts and weddings.
Tithi Vidya
The same rules, with NASA's positions for the sun and moon, worked out in your browser for any place on Earth.
The idea in four numbers
- 12°
- The moon moves this much further from the sun in one tithi. Thirty tithis make a moon month.
- 20–27 h
- How long a tithi lasts. So one can be skipped on the calendar, or fill two days.
- 11 days
- How much shorter twelve moon months are than a year of seasons.
- +1 month
- Added about every three years, adhika masa keeps Diwali in autumn and Holi in spring.
What I care about
Free, with no sign-up
No account, no payment, no app to install. Open the page and use it.
Private
Your birth details are worked out inside your own browser. They are never sent to me or anyone else.
Carefully checked
It uses astronomy data from NASA's Jet Propulsion Laboratory, and is tested against thousands of known results.
Open source
All the code is public, so anyone can see exactly how it works, or help make it better.
The goal
My vision is simple: I want people to actually use it.
If it helped you, share it with your family and friends. That is the biggest help you can give.
Say hello
Check out the other projects I've built, connect with me on LinkedIn, or send me a message.