Investment Calculator

Estimate future value using compound growth, optional recurring contributions, and contribution timing.

How to Use

  1. Enter your starting amount, expected annual return, and time period.
  2. Add optional recurring contributions and choose how often they occur.
  3. Select compounding frequency and whether contributions happen at the beginning or end of each period.
  4. Review future value, total contributions, interest earned, yearly breakdown, and Show Work.
Growth Projection
See how principal, contributions, and compound growth build over time.
Ready to calculate
Future Value
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Total Contributions
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Interest Earned
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Effective Annual Rate
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Balance Over Time

Enter values to generate projection.
Inputs & Settings
All calculations run in-browser. No uploads, no account required.
Starting principal before growth begins.
Expected average annual return before taxes and fees.
Supports whole years or partial years.
How often interest is applied each year.
Optional additional investment made on a schedule.
How often contributions are added.
Contribution Timing
Growth View
Used only when inflation adjustment is enabled.
Controls displayed rounding only.
Show Work (step-by-step)
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Work should show the base assumptions, periodic rate, number of periods, and the contribution timing method used.

Year-by-Year Breakdown

Projected ending balance, contributions, and interest by year.
Year-by-year investment growth breakdown
Year Starting Balance Contributions Interest Ending Balance
Enter values to generate yearly projection data.

Investment Growth Formulas

Quick answer: compound growth increases balance over time by applying returns to both principal and prior gains.

This calculator supports lump-sum growth plus optional recurring contributions.

  • Lump sum future value: FV = PV × (1 + r / n)n×t
  • Periodic rate: i = r / n
  • Number of compounding periods: N = n × t
  • Recurring contribution series: solved by periodic accumulation based on contribution frequency and timing
  • Interest earned: Future Value − Total Contributions
  • Real value (inflation-adjusted): Nominal Value ÷ (1 + inflation)t
Where PV = present value, FV = future value, r = annual return, n = compounding periods per year, and t = years.

FAQ

What is the difference between compounding and contributing?

Compounding grows the existing balance through returns. Contributions add new money to the balance on a schedule.

What does beginning vs end of period mean?

Beginning-of-period contributions are added before that period’s growth. End-of-period contributions are added after the growth for that period.

Does this calculator account for taxes or fees?

No. This tool estimates growth based on the inputs you provide. Taxes, investment fees, market volatility, and withdrawals can change real-world results.

Why can effective annual rate differ from the entered annual rate?

When compounding occurs more than once per year, the effective annual rate may be slightly higher than the nominal annual rate due to compounding frequency.

Tool Info

Last updated:

Updates may include improved calculation handling, contribution timing logic, display precision options, and yearly projection refinements.