Separate principal from interest
Compound growth applies each period’s rate to the accumulated balance. Simple interest applies it only to the original principal. At $1,000 and 5% annually for ten years, compound growth reaches $1,628.89, while simple interest reaches $1,500. The difference is $128.89, provided no deposits or withdrawals occur.
Compare like with like
Frequency comparisons hold the nominal annual rate constant. They do not establish that one actual investment is better than another. If two products state the same effective annual rate, changing the number of displayed compounding periods alone should not change their one-year growth factor.
Read interest by payment period
The detailed schedule separates deposits from growth at each reporting interval. Optional recurring deposits enter according to their own frequency and timing. The annual and daily comparison metrics keep all other entered assumptions fixed. To compare simple interest directly, set recurring deposits to zero; otherwise the timing of new principal needs an additional simple-interest convention.
Questions about this calculation
How can I check the inputs behind the result?
Open “Show calculation & assumptions” for the formula and timing conventions, then inspect the breakdown. Export CSV to keep the last calculated inputs and numerical results together.
Does this include taxes or changing market returns?
No tax calculation or variable market-return path is included. The task-specific assumptions above describe the scope. Calculated values are conditional on the inputs, not personalized recommendations.
Learn more
Start with the step-by-step future value formula guide.
Open the formula guide →How to calculate future value · Spreadsheet calculations · All learning guides
Use these figures to explore assumptions. Actual interest, returns, fees, taxes and purchasing power can differ.