Estimate the repayment tenure for a loan, given the principal, rate and the EMI you plan to pay.
Uses the EMI formula in reverse, with logarithms, to find the number of months needed.
Tenure: n = ln(EMI ÷ (EMI − P×r)) ÷ ln(1+r)
Why does it say my EMI can never repay the loan?
If your chosen EMI is equal to or less than the monthly interest on your loan, your loan amount never goes down. You would be paying interest forever, without ever touching the actual loan. Your EMI must be more than the monthly interest for the loan to be paid off.