Compound interest is interest earned on interest. How often it is added - daily, monthly, quarterly - changes the effective yearly rate shown on the right.
Switch 'Regular amount' to Withdrawal to see how long a corpus lasts if you take a fixed amount out every month - the same question a systematic withdrawal plan (SWP) answers.
How it is worked out
Balance = P × (1 + r / n)n × t for a lump sum, where r is the yearly rate, n the times a year interest is added and t the time in years. Regular amounts are added or taken month by month.
Questions
How long will my money last?
Choose Withdrawal, put in your corpus, the amount you take each month and a realistic return. If it runs out, the page says in which month.
What does the inflation box do?
It shows the final balance in today's money - what it would buy now.