Accurate Interest Calculator
A Brief Introduction to the Interest Calculator
This calculator calculates the interest owed between any two dates. It supports both simple interest and compound interest, with more than a dozen available compounding options. It also supports negative interest rates.
Because this calculator performs date-based calculations, it is well suited for determining interest owed on a debt. You can calculate accrued interest from any date for which the balance is known. More details appear below the calculator…
Related: If you need to calculate interest on a series of payments, deposits, or withdrawals, use the Future Value of an Annuity Calculator.
The Calculator-Calculate Interest Between Any Two Dates
To set your preferred currency and date format, click the “$ : MM/DD/YYYY” link in the lower-right corner of any calculator.
Information
What is compound interest?
Compound interest is interest calculated on both the original principal and on any previously accrued interest. If you pay compound interest or earn compound interest, interest from earlier periods also earns interest.
For example, if the annual interest rate is 2% and you start with $1,000, you will earn or owe $20 after one year (using annual compounding). After two years—assuming no withdrawals or additional payments—the interest earned in the second year will be $20.40, not $20. This is because the first year’s interest also earned interest.
This process is called compounding. It continues as long as the funds remain invested or the borrower continues to owe the debt.
If you are an investor, compounding increases your returns. If you are a borrower, compounding increases your cost—especially if you miss a payment or your payment does not cover the full interest due.
What is simple interest?
Simple interest is calculated only on the original principal amount. For a loan, interest is not charged on any unpaid interest. If you are a borrower, paying simple interest is generally less costly. According to