I did a quick search in google and there seems to be a healthy amount of traffic for different types of calculators in India (e.g.: loan calculator, love calculator, etc..).
I have no idea what the competition is in India for those keywords. Nor do I know anything about the Indian market or how products or advertising sell online there.
So for those reasons, I wouldn't want to hazard an appraisal, but I do think it's worth keeping and developing.