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Part of the Finance collection — 4 tools available

Finance

Compound Savings Calculator

Calculate how your monthly savings grow with compound interest over time. See total contributions, interest earned, and future value of regular deposits.

About This Calculator

Consistent saving combined with compound interest is the most reliable path to wealth building, yet most people dramatically underestimate how much their regular deposits will grow over time. Even modest monthly contributions grow into substantial sums — $500 per month at 6% annual return becomes over $145,000 in 15 years and $348,000 in 25 years, with interest accounting for roughly half the total. Starting early matters enormously: beginning just 5 years sooner can add tens of thousands to your balance. Our compound savings calculator shows future value, total interest earned, and the powerful effect of starting now.

The Formula Behind This Calculator

FV = PMT * [((1+r)^n - 1) / r] Starting early dramatically increases balance Consistency beats amount.

Understanding the math helps you verify results and make better decisions for your project.

How to Use

  1. 1Enter your planned monthly deposit amount.
  2. 2Set the expected annual interest rate (6% is a reasonable long-term average for balanced investments).
  3. 3Choose your time horizon in years.
  4. 4Add any existing savings as your starting balance.

When to Use

  • Planning long-term savings goals like retirement or a down payment.
  • Seeing the impact of increasing your monthly savings amount.
  • Comparing how starting earlier vs saving more affects your outcome.

Tips

  • Starting 10 years earlier can double your final balance thanks to compounding.
  • A 1% increase in annual return adds 15-25% more to your final balance over 20+ years.
  • Automate your savings — set up automatic transfers on payday so you never miss a deposit.

FAQ

What interest rate should I use?

High-yield savings: 4-5%. Conservative investments: 5-7%. Stock market average: 7-10%. Use 6-7% for long-term diversified portfolios, and remember this is an average with year-to-year variation.

How much should I save per month?

Financial experts recommend saving at least 20% of income. If that is too much, start with whatever you can and increase by 1% each month. Even $100/month builds significant wealth over decades.

Does inflation affect my real returns?

Yes. At 6% returns and 3% inflation, your real return is about 3%. Consider using an inflation-adjusted rate (nominal rate minus inflation) to see purchasing power growth.

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