How to Calculate Compound Interest
What regular contributions become over time once compounding does the work.
How this number is built
Calculating it yourself
Step 1
Enter what you already have as the starting amount.
Step 2
Add the contribution you can genuinely sustain every month, not an aspirational one.
Step 3
Use a conservative return — long-run diversified equity returns are commonly modelled between 6% and 8% nominal.
Step 4
Set the time horizon; this is the input with the largest effect on the outcome.
Step 5
Check the inflation-adjusted figure, because that is what the money will actually buy.
What people ask next
Does compounding frequency matter much?
Less than people expect. Moving from annual to monthly compounding adds a small amount; the contribution rate and time horizon matter far more.
Should I use nominal or real returns?
Model nominal and then look at the inflation-adjusted line. Mixing the two in one input is the most common error here.
Searches this page answers
| Related search | Goes to |
|---|---|
| compound interest calculator | Compound Interest Calculator |
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| investment growth calculator | Compound Interest Calculator |
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