Interest Calculator

Calculate simple and compound interest on your investment

How to use this tool

Investment Details

$
%
years
Final Amount
$5,675.00
after 3 years
Interest Earned
$675.00
Simple interest

Investment Breakdown

Principal
$5,000.00
Interest
$675.00

Calculation Details

Interest TypeSimple Interest
Effective Annual Rate4.50%
Return on Investment13.50%

Simple vs Compound Interest

Simple interest is calculated only on the principal amount, while compound interest is calculated on both the principal and accumulated interest. Compound interest grows faster over time, especially with more frequent compounding periods. Canadian banks typically calculate interest on savings accounts using daily compounding with monthly posting. This means interest accrues every day based on your closing balance, and the accumulated interest is deposited to your account once a month. GICs (Guaranteed Investment Certificates) usually compound annually, though some offer monthly or semi-annual compounding. To compare savings accounts and GICs effectively, look at the Effective Annual Rate (EAR) rather than the nominal rate. A savings account advertising 4.00% compounded daily actually yields 4.08% annually, which may outperform a GIC at 4.05% compounded annually. To maximise your interest income in Canada, consider holding your savings in a TFSA (Tax-Free Savings Account), where all interest earned is completely tax-free. High-Interest Savings Accounts (HISAs) offered by online banks like EQ Bank, Tangerine, or Simplii often offer rates 1-2% higher than the Big Five banks. The Bank of Canada's overnight rate directly influences savings rates: when the Bank raises its rate, HISA and GIC rates typically follow within weeks. Remember that interest income held outside registered accounts (TFSA, RRSP) is taxed at your full marginal rate, making it the least tax-efficient form of investment income in Canada.

Frequently Asked Questions

Last updated: July 2026

The overnight rate is the interest rate at which major banks lend to each other overnight. It directly influences the prime rate that banks charge consumers. When the Bank of Canada raises the overnight rate, variable-rate loans, mortgages, and lines of credit become more expensive. Savings account and GIC rates also tend to rise, benefiting savers.

Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus all previously earned interest, creating a snowball effect. For example, $10,000 at 5% simple interest earns $500 per year forever. With annual compounding, year one earns $500, year two earns $525, year three earns $551.25, and so on.

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Educational tool - estimates only. Not individualized financial, investment, tax, or legal advice. Using it does not create an advisor-client relationship. Rules and figures change; verify against current CRA sources and consult a qualified professional. Editorial policy