There are two numbering systems that I have to deal with daily.
One is the Indian numbering system, and the other is the western system.
Indian system is in thousands, lakhs, crore, lakh-crore/arab, while the western system is in thousands, millions, billions, trillions.
Then there is the comma!
10 lakh is equal to 1 million but expressed as 10,00,000 in the Indian system and 1,000,000 in the western system.
Now, if these numbers are currencies, specifically rupees(INR) and dollars($), there is a foreign exchange rate.
There are too many moving parts to convert numbers from one system to another. I found myself googling every time for a converter, but these converters are too sophisticated and offer a lot of units that I don't care about + terrible user interface.
I wrote a simple converter that does one thing very well. It takes just one input and converts it to the Indian number system as well as the western system. You can find it here: https://croretobillion.netlify.app/
It also shows value in Rs and $ at the same time, using the real-time exchange rate from here: https://exchangeratesapi.io/