You need to save _________ in ______ years to live off it for the next ______ years.

Things to note here:
1. This calculator also takes into account a nominal interest of 5% earned by your savings from the time of retirement. This is a pretty useful factor. Came in as a suggestion from some friends of mine.
2. This is calculated with inflation at 6%.
3. The formula is such that it leaves you with a extra 10 Lacs after your retirement period. For emergency sake.
4. Assumes that you are earning nothing post retirement. This might not be true, if you have rent coming in, or some royalty from that book that you are going to publish soon. :)
Disclaimer: I'm no financial advisor, I just read things online and built this with some assumptions. So don't depend on this.