Simple interest is calculated only on the principal, not on interest that has already built up. That makes it easy to work out, and it’s common in short-term loans and deposits.

It estimates the interest you’ll earn or pay on a fixed principal over a set time. Loans, deposits and basic financial planning are the usual uses.

Multiply the principal by the rate and the time in years, then divide by 100. The formula is I = (P × R × T) ÷ 100. Finmarra’s calculator does this for you and also gives the maturity value, which is the principal plus the interest.

You’ll see it in short-term loans, gold loans, some personal borrowing and certain fixed-return deposits. Any arrangement that charges a flat rate on the original amount fits the pattern.

No. Interest is worked out on the original principal every time, so it never earns interest of its own.

Yes, as long as the interest is charged at a flat rate. It works for personal loans, gold loans and short-term borrowing of that kind.

You can, where the deposit pays interest on a non-compounding basis. Many FDs compound, so check how your bank calculates before relying on the number.

The calculator takes the tenure in years. It then shows a month-wise growth table, and the monthly interest equals the total interest divided by the number of months.

No. It shows interest before any tax. Interest on deposits can be taxable, so check the rules that apply to you or ask a tax professional.

Yes. Change the rate or the tenure and look at the new result, or run a few scenarios one after another. Download each one if you want to compare them later.

Not by the calculator. It gives an estimate from your inputs. What you actually get depends on the terms set by your bank or lender, so confirm those with them.

Simple interest is calculated on the principal alone. Compound interest is calculated on the principal plus the interest already earned, so the amount grows faster as time passes.

There’s no single right answer, since it depends on your goal and the rate on offer. With simple interest, each extra year adds the same amount, so a longer tenure raises your total in a predictable way. Try a few tenures in the calculator and see what suits you.

Students, borrowers and depositors who want a quick interest figure without working through the formula by hand.

It’s quicker and there’s less room for mistakes. You also get things a manual sum won’t give you, like the month-wise table and downloadable PDF and Excel files.