Interest Calculator for Exact Days

This simple interest calculator calculates interest between any two dates. Per Dictionary.com simple interest is "interest payable only on the principal". Interest is never earned or collected on previous interest. More below...»

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Simple interest is the interest calculation method that is least beneficial to savers and the most beneficial to borrowers. But note, if payments on a debt are paid as frequently as the compounding and the payment covers the interest due, then even if the terms of the loan call for compounding, there will be no impact on the total amount paid because at no point will there be any unpaid interest.

U.S. Rule Loan & Negative Amortization

When the terms of a debt call for a simple interest calculation, if a payment does not cover the interest due, the unpaid interest must be tracked separately from the unpaid principal balance (also known as the US Rule). We believe that our Time Value of Money Calculator is the only online financial calculator that gives users this option and creates a schedule that shows the unpaid interest balance.

Enter an amount and a nominal annual interest rate.

Date Math: If you change either date, days between dates will be calculated. If you enter a positive number of days, the end date will be updated. If you enter a negative number of days the start date will be updated.

The above means you can calculate interest for a specific number of days and not worry about what the dates are. If you need to know the interest for 31 days, then enter 31 for the number of days and don't worry about the dates.

Set the compounding and days-in-year. Click "Calc". Interest and future value are calculated (FV is starting amount plus the interest.) **Annual percentage yield** is used for comparing investments. It is the rate institutions must quote in the US for interest bearing accounts. The holder of such an account can use the *APY* to compare accounts.

Interest is calculated based on the number of days. In this case, the amount of interest will be different for February and March.

This site also has a "Compound Interest Calculator"

Please tell me how you use this calculator. Are you using it personally or professionally? What feature is important to you? If it didn't meet your needs, why? Your feedback will help me make improvements. Complete sentences aren't necessary! :)

This is exactly what I needed to calculate interest for an account that is past due. I work in the legal field and needed to find out what would be owed to date on a previous judgement.

This is perfect – Exactly what I needed to calculate interest on my monthly invoices. I used it on my job. Thanks

Teaching kids about the various methods of interest solutions/problems applied, fantastic.

I owe my brother some money and needed to figure the interest too. Thanks!

It would be helpful if this calculator could also generate an amortization table for monthly payment amounts.

There are a number of calculators that support simple interest on this site that will also create a viewable/printable amortization schedule. Here are 3 such calculators:

loan calculator

amortization schedule

ultimate financial calculator

There are reasons to use one over another. If you care to tell me what you need to accomplish, perhaps I can provide a more specific recommendation?

This works if you are receiving one lump payment but it does not if you have multiple or more than one payment.

Do you have a calculator for that?

Yes, I’m sure I do.

But I’m not 100% sure I’m clear on what you mean. You use the word "payment." Is this a loan cash flow, and the balance is approaching 0? If so, then try this loan calculator.

Or is this a savings or investment cash flow and the balance is growing? Then try this savings calculator.

You can also try this time value of money calculator. This one is the most flexible. It works with both loans and investments. Scroll down the page for 25 tutorials.