Credit Card Interest & Payoff Calculator
Why the minimum due takes years — and what paying more saves.
What you owe over time
Payment schedule
How the interest is charged
Results are estimates for general information and planning, not financial advice. Banks and institutions may calculate differently (rounding, fees, rate changes). Confirm figures with your lender or a qualified adviser before deciding.
About the Credit Card Interest & Payoff Calculator
Enter the balance on your credit-card statement, the card’s interest rate — a monthly rate such as 3.75%, or an APR — and what you could pay. The calculator works out, statement by statement, how long the balance takes to clear and what it costs if you pay only the minimum due, a fixed amount each month, or the amount that clears it in the months you choose.
It charges interest the way cards do: daily, on the balance from the day it arose, with 18% GST on the interest in India, no interest-free period on new spending while you carry a balance, and the interest that still appears on the bill after the one you pay in full. The schedule shows every payment, and nothing you enter leaves your browser.
How to use it
- Type the total due from your latest statement and the interest rate from your card’s terms, as a % a month or as an APR. Keep 18% GST ticked for an Indian card.
- Enter a fixed payment you could make every month, and the number of months you would like to be clear in.
- If you keep using the card, enter your new spending each month.
- Open Minimum due and payment day to match your card: how its minimum amount due is worked out, the smallest minimum, and how many days after the statement you pay.
- Compare the three plans, read the schedule for each, and copy the summary or download the schedule as CSV.
Examples
Minimum due: interest, GST and fees + 2% of the rest, at least ₹200
Minimum due only: 167 payments (13 years 11 months), ₹1,08,044 of interest and GST · ₹5,000 a month: 15 payments, ₹16,032 · to clear it in 36 months: ₹2,708 a month, ₹46,478
In 8 of the early months the minimum due (up to ₹3,117) is more than ₹2,708, so those payments are the minimum due — the card requires at least that.
424 payments — 35 years 4 months — and ₹3,02,687 of interest and GST, because 5% of the total due is only a little more than the month’s interest and GST
45% a year as an APR; 55.5% a year once interest is charged on interest; 65.5% a year with 18% GST on that interest (GST itself is not charged interest)
₹93.75 of interest on each month’s spending (no interest-free period while the balance is carried) — 30 payments to be interest-free again
Common uses
- See what paying only the minimum due really costs, and how long it takes.
- Find the monthly payment that clears your card in a year, or in three.
- Understand why there is interest on your bill after you paid the last one in full.
- Decide between paying the card down and converting it to an EMI or a personal loan — then compare loans in the debt payoff planner.
How card interest is charged
Under the Reserve Bank of India’s Master Direction – Credit Card and Debit Card – Issuance and Conduct Directions, 2022:
- The interest-free period runs from the purchase to the payment due date only if you pay the entire outstanding by the due date (para 3(a)(xvi)); it is suspended if any balance of the previous month’s bill is outstanding (para 9(b)(iii)). Once it is lost, interest may be charged from the date of each transaction on the outstanding amount (FAQ 6).
- Interest is charged only on the outstanding amount, adjusted for payments, refunds and reversed transactions (para 9(b)(vi)) — so a payment cuts the interest from the day it is made.
- Unpaid charges, levies and taxes — GST included — must not be capitalised for charging interest (para 9(b)(ii)).
- The minimum amount due must be set so that there is no negative amortisation: it covers at least the interest and charges billed (para 9(b)(ii) and the Annex).
- Cards must quote the APR for each situation (para 9(b)(i)), and bills must give at least a fortnight before interest starts (para 10(a)).
Source: RBI Master Direction.
The formula, and SBI Card’s worked examples
Daily rate = APR ÷ 365, where the APR is the monthly rate × 12 (3.75% a month = 45% a year). For each cycle:
- interest = daily rate × (statement balance × days to your payment + balance after payment × days to the next statement);
- when the interest-free period is lost, the days start from the purchase dates;
- GST = 18% of the interest, kept outside the interest-bearing balance; payments clear GST first, then the balance.
The calculator reproduces the worked examples in SBI Card’s most important terms and conditions. In one, a ₹6,000 purchase on 15 March is billed on 2 April with a ₹500 annual fee and ₹90 of tax; the ₹710 minimum due paid on 22 April clears the fee, the tax and ₹120 of the purchase, so the interest is 45% × 38/365 × ₹6,000 + 45% × 11/365 × ₹5,880 = ₹360.84. In another, after a ₹50,000 purchase on 7 May and the ₹1,000 minimum paid, the next bill shows ₹2,267.26 of interest (the same figure as the formula gives when the ₹1,000 is paid on 2 June; SBI does not print that date), ₹408.11 of GST and a minimum due of GST + interest + 2% of ₹49,000. The same document charges 18% GST on fees, interest and charges (CGST 9% + SGST 9%, or IGST 18%). A cycle is taken as 365 ÷ 12 days and new spending as spread evenly through the month.
Why the minimum due takes so long
Most of a minimum payment is the month’s interest and GST; only the rest reduces what you owe. At 3.75% a month plus GST, ₹50,000 adds about ₹2,200 of interest and GST in the first month, and a minimum of ₹1,000 now and about ₹3,200 next month leaves the balance almost where it started. The RBI requires every statement to warn that paying only the minimum makes repayment stretch over months or years (para 9(b)(iii)).
US card statements must show a similar minimum payment warning, how long paying only the minimum would take and what it would cost, and the monthly payment that clears the balance in 36 months (12 CFR 1026.7(b)(12)). Set Or clear it in to 36 to see the same kind of figure for your card.
Limitations
- A statement cycle is taken as 365 ÷ 12 days and new spending as spread evenly; real cycles are 28–31 days, so a bank’s figures can differ by a few rupees.
- Cash withdrawals (on SBI Card, for example, they have no interest-free period), EMI conversions, annual fees, late fees and over-limit charges are not included.
- The rate stays the same for the whole plan. Issuers may charge different rates depending on your repayment record (RBI Master Direction, para 9(a)).
- The minimum due follows the rule you choose; check your card’s MITC for its exact rule.
- The minimum due on your latest statement is worked out from the balance alone, as if no interest or fees were billed on it; if they were, the minimum printed on your statement is higher. From the next statement on, the interest and GST billed are included.
- When you ask to clear the card in a number of months, months whose minimum due is higher than the amount worked out are paid at the minimum due, as the card requires; the plan says how many.
Privacy
Everything is calculated in your browser. Nothing you enter is uploaded or stored.
Frequently asked questions
How is credit card interest calculated?
Daily, at the APR ÷ 365, on the balance you carry — from the date of each purchase once the interest-free period is lost, and on the reduced balance after each payment. In India 18% GST is added to the interest. A card that charges 3.75% a month (45% a year) charges ₹1,862 of interest and ₹335 of GST in a month on ₹50,000 after a ₹1,000 payment on day 20.
What happens if I pay only the minimum amount due?
You avoid late fees, but the rest of the balance is charged interest, you lose the interest-free period on new purchases, and repayment can take years. On ₹50,000 at 3.75% a month, a minimum of interest, GST and fees plus 2% of the rest takes almost 14 years and costs about ₹1.08 lakh of interest and GST.
Why is there interest on my bill when I paid the last one in full?
If you were carrying a balance before, interest runs on it from the statement date until the day you pay, and that interest appears on the next bill. Pay that bill in full too, and the card is interest-free again.
Is GST charged on credit card interest?
Yes, in India: 18% GST on the interest, fees and charges (CGST and SGST of 9% each, or IGST of 18%), as card issuers’ terms state. Under the RBI’s rules, unpaid GST and charges are not themselves charged interest.
What is the interest-free period on a credit card?
The days between a purchase and the payment due date during which no interest is charged — but only if you pay the total amount due by the due date. If any of last month’s bill is still outstanding, the interest-free period is suspended and new purchases are charged interest from the day you make them.
How do I convert a monthly credit card rate to an annual rate?
Multiply by 12 for the APR: 3.75% a month is 45% a year. Because unpaid interest is itself charged interest each month, the effective yearly cost is higher — 55.5% — and with 18% GST on that interest it is about 65.5%. GST is added once: unpaid GST is not charged interest.