Compound Interest Calculation in Excel
Create a compound interest calculation in Excel for a lump sum plus regular deposits. The formula builder returns both the calculated future value and a copy-ready FV formula.
Written and checked by TheToolNet Editorial Team · Last reviewed: September 27, 2026 · Editorial method
Use =FV(rate/frequency, years*frequency, -deposit, -principal, 0). The rate and period count must use the same frequency.
Build and check the Excel formula
Recommended worksheet layout
| Cell | Meaning | Example |
|---|---|---|
| B2 | Starting amount | 10000 |
| B3 | Annual rate | 6% |
| B4 | Years | 10 |
| B5 | Periods per year | 12 |
| B6 | Deposit per period | 100 |
| B7 | Future value | =FV(B3/B5,B4*B5,-B6,-B2,0) |
Why the minus signs appear
Excel financial functions use cash-flow signs. Money paid into the account is negative from your perspective, while the resulting future balance is positive. Microsoft documents the syntax as FV(rate,nper,pmt,[pv],[type]) and recommends consistent period units. See Microsoft's FV function reference.
Compounding without deposits
For a single principal, use =B2*(1+B3/B5)^(B4*B5). The FV version is more convenient when you also contribute a constant amount. For a reverse goal calculation, use the backwards compound interest calculator.
Common spreadsheet errors
- Entering 6 instead of 6% while also dividing by the frequency.
- Using an annual rate with a monthly period count without dividing by 12.
- Mixing monthly deposits with quarterly periods.
- Omitting the negative cash-flow signs and getting a negative future value.
Frequently asked questions
What does the final zero mean?
It means deposits occur at the end of each period. Use 1 for beginning-of-period deposits.
Does Excel predict the return?
No. It applies the constant rate you enter. Actual savings or investment results can vary.