Compound interest calculator and investment growth calculator
A compound interest calculator estimates future value from principal, recurring contributions, number of periods, and return per period with a simple compound interest, investment growth, or future value model for savings and investing.
Run this scenario on-page
Use the dedicated calculator below to test this exact page topic without switching assets or leaving for another tool.
Use this for general future value estimates when you want to model a steady return assumption rather than a market-history backtest.
Future value
$116,639
Total contributed
$70,000
Profit
$46,639
Total return
66.63%
What this page helps with
Project long-term savings and investing outcomes from a fixed return assumption.
What this page helps with
Include recurring contributions and choose whether they are added at the beginning or end of each period.
What this page helps with
Use this calculator when you want a clean future value estimate without tying the result to SPY or QQQ market history.
What this page is for
A compound interest calculator, also called an investment growth calculator or future value calculator, estimates future value from a starting principal, recurring contributions, a number of periods, and an assumed return per period.
Why this page is easier to trust
What is disclosed
The page states that results come from user assumptions rather than real SPY or QQQ market history.
What is disclosed
It separates principal, recurring contributions, contribution timing, and assumed return per period so the math is easier to audit.
What is disclosed
The output shows total contributions and profit separately so users can tell how much of the final value came from deposits.
Step-by-step
Step 1
Enter your starting principal, recurring contribution amount, number of periods, and the expected return per period.
Step 2
Choose whether contributions happen at the beginning or end of each period, since that changes how long each deposit compounds.
Step 3
The calculator returns estimated future value, total contributed capital, total profit, and total return under the assumptions you entered.
Quick takeaway
Use this page for forward-looking planning when you want to model savings growth from assumptions, not reconstruct what a real ETF did in a historical period.
Learn more before you compare results
How to Use a Compound Interest Calculator Correctly
Understand inputs, assumptions, and contribution timing before trusting the output.
Lump Sum vs DCA Explained for Long-Term Investors
Compare one-time investing and recurring contributions from a practical decision-making angle.
Future Value Calculator With Monthly Contributions
See how monthly deposits, periods, and assumptions work together in forward-looking planning.
What Is Annualized Return?
Understand the yearly growth rate metric users often see next to final value and profit.
Warren Buffett Value Investing Basics
Learn long-term investing principles that connect naturally with compounding and patience.
Common questions
What inputs does a compound interest calculator need?
The standard inputs are principal, recurring contribution, number of periods, and return per period. Contribution timing is also helpful.
Is this the same as a historical SPY or QQQ calculator?
No. This tool projects outcomes from a fixed rate assumption, while the ETF tools aim to backtest using actual historical prices.
Why does contribution timing matter?
Contributions made at the beginning of each period have more time to compound than contributions made at the end.
Can this page be used as an investment growth calculator?
Yes. This page works as an investment growth calculator because it estimates how principal and recurring contributions could grow under a fixed return assumption.
Is a compound interest calculator the same as a future value calculator?
In many personal finance and investing contexts, yes. Both are commonly used to estimate how money can grow over time under a set of return assumptions.
Can this page be used as a future value calculator with monthly contributions?
Yes. If your period setting matches a monthly assumption, the page can function as a future value calculator with monthly contributions.
What is the difference between a compound interest calculator and a future value calculator?
They are often very similar. In practice, both are used to estimate how money grows over time, especially when contributions and compounding are part of the calculation.
Can this page estimate compound growth for savings goals?
Yes. It is useful for savings and investment planning when you want to test how regular contributions and a chosen rate of return affect the final amount.
Does this page explain what assumptions drive the final value?
Yes. The calculator is paired with plain-English guidance so users can understand contribution timing, compounding periods, and assumed return rates before trusting the result.
Why should I trust this calculator more than a simple online savings estimate?
It shows the core inputs clearly and separates total contributed money from total profit, which makes the result easier to inspect and compare.