0% Intro APR Calculator
Find the monthly payment required to clear your balance before the promotional 0% period ends, and see the cost if you fall short.
Last updated September 2026 · Reviewed by the CalcMyCard editorial team
Divide your balance by the number of months in your 0% promotional period to find the flat payment that guarantees you reach zero before interest kicks in. Enter your numbers below to check your plan.
A 0% intro APR offer is only free money if you actually pay off the balance before the clock runs out. This calculator tells you exactly what payment you need to make that happen — and what it will cost you if you fall short.
The one number that matters most
Your balance divided by your number of promotional months is the flat payment required to hit exactly $0 right when the promo ends. Pay less than that, and you'll carry a remainder into the card's regular (often much higher) go-to APR. Pay that amount or more, and the entire balance costs you $0 in interest.
Watch out for deferred interest
Some 0% promotions — common on store cards and some retail financing — are "deferred interest" offers rather than true 0% APR. If you don't pay the full balance by the deadline, some of these plans charge interest retroactively back to the original purchase date, not just from the point where the promo ended. Always check your specific card's terms for this distinction; the calculator above assumes a standard (non-retroactive) promotional period unless you tell it otherwise via your inputs.
What if your budget can't hit the required payment?
If the required flat payment above is more than you can comfortably afford, it's worth comparing what a balance transfer to a longer promotional period, or a fixed-rate consolidation loan, would look like instead — see the Balance Transfer Calculator and Debt Consolidation vs. Balance Transfer Calculator.
Frequently Asked Questions
What happens if I don't pay off my balance before the 0% APR period ends?
Any remaining balance begins accruing interest at the card's standard go-to APR — and on some cards, deferred-interest promotions can retroactively charge interest back to the original purchase date if not paid in full by the deadline. Always check your card's specific terms.
How do I make sure I pay off my balance in time?
Divide your balance by the number of months in the promotional period — that's the minimum flat payment you need each month to reach zero exactly when the promo ends. This calculator does that division for you and flags if your planned payment falls short.
This calculator provides estimates for educational purposes only and is not financial, tax, or legal advice. Your card issuer's actual calculation may differ slightly based on its compounding method, fees, and grace period rules — always confirm against your official statement.