Compound Interest Calculator

See how your investments can grow over time with the power of compound interest. Perfect for TSP projections and retirement planning.

How to Use This Calculator

• Enter your initial investment amount
• Set your monthly contribution (use negative for withdrawals)
• Choose your time horizon and expected return rate
• Add a variance range to see best and worst case scenarios
• View detailed yearly breakdown and visual charts

🔒 Your Privacy Protected: For your security, we do not store any of your financial information. All calculations are performed in your browser and cleared when you close it.

Initial Investment

Monthly Contribution (or Drawdown)

Use a negative number for drawdowns (e.g., -500).

Length of time in years

Estimated interest rate

Interest rate variance range

Compound frequency

In 10 years, you will have

$0.00

Contribution vs. Interest Growth

Results Breakdown

Year	Total Contributions	Total Interest	End Balance

Important Notes

This calculator assumes a constant rate of return, which may not reflect actual market conditions
The variance range shows potential outcomes based on different return scenarios
For TSP projections, consider using historical fund returns as your baseline
Remember to account for inflation when planning for retirement
This tool is for educational purposes only - consult a financial advisor for personalized advice