Simple Interest Calculator

Interest earned or owed using the straight-line simple interest formula.

%
yrs
Total amount
$5,900.00

$900.00 interest

Principal
$5,000.00
Interest
$900.00
Per year
$300.00
Show the working
  1. 1Interest = $5,000.00 × 6% × 3 years = $900.00
  2. 2Total = $5,000.00 + $900.00 = $5,900.00
Formula
I = P × r × t ÷ 100

How it works

Simple interest is charged only on the original principal — unlike compound interest, earned interest never itself earns interest.

Example

$5,000 at 6% for 3 years earns $900, giving $5,900.

About the Simple Interest Calculator

Interest earned or owed using the straight-line simple interest formula. It sits in the Finance & Loans section of NWS Calc, a free collection of calculators that run entirely in your browser. There is no signup, no paywall and no tracking — open the page, enter your numbers, get an answer.

Frequently asked questions

Is the Simple Interest Calculator free to use?
Yes. Every calculator on NWS Calc is completely free, with no signup, no usage limits and no ads.
Does my data leave my device?
No. The Simple Interest Calculator runs entirely in your browser using JavaScript. Nothing you type is uploaded, logged or stored on a server.
Can I use the Simple Interest Calculator on my phone?
Yes. The page is fully responsive and works in any modern mobile or desktop browser — there is nothing to install.
What else is in Finance & Loans?
Loans, mortgages, interest, savings and investment returns. You can browse the full Finance & Loans category for related calculators.

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