Compound interest guide
The formula
Without contributions:
A = P ร (1 + r/n) ^ (nรt)
P = principal ยท r = annual rate ยท n = compounds/yr ยท t = years
The Rule of 72
Divide 72 by your annual rate to estimate years to double your money. At 4% โ 18 years. At 6% โ 12 years. At 9% โ 8 years.
Compounding frequency
Daily (365ร/yr)Highest yield
Monthly (12ร/yr)Most savings accounts
Quarterly (4ร/yr)Some GICs & bonds
Semi-annual (2ร/yr)Government bonds
Annually (1ร/yr)Simple GICs
FAQ
What is compound interest?
Interest calculated on both your principal and the accumulated interest from previous periods โ causing exponential growth over time.
TFSA vs RRSP for compounding?
TFSA growth is completely tax-free โ ideal for long-term compounding. RRSP growth is tax-deferred; you pay tax on withdrawal but get a deduction now.
What are good Canadian GIC rates in 2026?
Competitive GIC rates range from 3%โ5% depending on term. Online banks and credit unions often beat the Big Six.
Is my data stored?
No โ everything runs in your browser. Nothing is uploaded or saved anywhere.