Compound Interest Calculator

Project your savings growth with compound interest and optional recurring contributions. Choose compounding frequency and export a yearly projection.

Starting Balance

Initial amount you invest/save today.

Recurring Contribution Contribution Frequency Monthly Yearly No recurring contribution

How often you add money after the start.

Annual Interest Rate (APR, %)

Nominal annual rate (not APY).

Compounding Frequency Annually (1×/yr) Semi-annually (2×/yr) Quarterly (4×/yr) Monthly (12×/yr) Daily (~365×/yr)

How often interest is added to your balance.

Time Horizon (Years)

Total years to grow.

Start Month (optional) January February March April May June July August September October November December

Only affects the table’s month markers.

Tip: Press Enter or click Calculate.

Calculate Reset

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Show yearly projection

Year	Start Balance	Contributions	Interest	End Balance

Download CSV

How to use

1. Enter your Starting Balance.
2. Add a Recurring Contribution and pick the frequency (monthly or yearly) or choose No recurring contribution.
3. Set the Annual Interest Rate (APR), Compounding Frequency, and Years.
4. Click Calculate. Open Yearly projection to see the growth per year and export a CSV.

Benefits

• Plan savings faster with clear final balance and interest earned.
• Flexible compounding (annual to daily) and contributions (monthly/yearly/none).
• Year-by-year breakdown to track progress and milestones.
• CSV export for spreadsheets or sharing with an advisor.

How it calculates

The calculator simulates growth month-by-month for accuracy across different contribution and compounding patterns.

For compounding n times per year with no contributions:
  FV = P · (1 + r/n)^(n·t)

With regular contributions (PMT) at frequency m (e.g., monthly),
we simulate in monthly steps. Each step adds contributions
then applies interest when a compounding period ends. This
closely matches real-world posting of interest and contributions.
        

Short disclaimer

This calculator provides estimates only and is not financial advice. Interest rates, compounding rules, posting timing, taxes, and fees vary by institution and may change outcomes. Consult your bank or advisor for exact terms.