Credit Card Interest Calculator
How much interest a balance costs per day, per month and over a billing cycle at your APR.
Tool inputs stay in your browser · optional AI search sends your query
Good to know: Daily rate = APR ÷ 365; cycle interest ≈ balance × daily rate × days. Many cards compound daily on the average daily balance. Estimate for planning only, based on the numbers you enter. Your bank or provider’s statement is the final word.
How to use it (step by step)
- 1Fill in the boxes: “Balance”, “APR (%)”, “Days in billing cycle”. Example numbers are already there so you can see how it works; replace them with yours.
- 2The result updates instantly as you type (on a phone it is below the boxes).
- 3The bold line is the main answer. Tap Copy next to any value to copy it.
Words to know
- APR
- Annual Percentage Rate: the yearly interest rate. Philippine cards often show a monthly rate instead; ×12 gives the APR.
- Interest
- The extra money you pay for borrowing, like a rental fee for using someone else’s money.
- Percentage
- A part out of 100. 25% of 200 = 50.
- Average (mean) / median
- Average = add everything and divide by how many. Median = the middle value when sorted; it is not pulled by extreme values.
- Compound interest
- Interest that also earns interest over time, so savings (or debt) grow faster and faster.
- DOCX (Word file)
- The file type Microsoft Word, Google Docs and WPS use for editable documents.
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