Investment Calculator
Project the future value of a starting amount plus monthly contributions at a stated annual return. Choose annual, semiannual, quarterly, monthly, or daily compounding.
Investment Calculator tool
About the Investment Calculator
Deposits are added at each month end. The selected compounding convention is converted to an equivalent monthly rate so a 12% nominal rate compounded monthly does not silently become 1% simple interest treated as something else.
This is the same growth engine as the compound interest calculator, framed as an investment. It is not a forecast of any fund, and it does not deduct advisory fees or taxes.
How the Investment Calculator works
Without deposits the balance is P × (1 + R/k)^(k t). With monthly deposits, an equivalent monthly rate i is used and each contribution grows from the month it is added.
i = (1 + R/k)^(k/12) − 1
FV = P × (1 + i)^N + C × [((1 + i)^N − 1) ÷ i]
Example
$1,000 at a nominal 12% compounded monthly for one year with $100 deposited each month end grows to $2,395.08.
How to Use the Investment Calculator
- Enter the starting amount.
- Enter the monthly contribution (use 0 to grow a lump sum only).
- Enter years (whole months).
- Enter the annual return and compounding frequency.
- Read future value, contributions, and the yearly table.
Investment Calculator Examples
Lump sum only
$10,000 at 7% compounded monthly for 10 years with $0 contributions is about $20,096.
Monthly investing
$200 a month for 10 years at 7% monthly compounding, starting from $0, is the annuity part of the formula alone.
0% return
At 0%, future value is starting amount plus $200 × 120 if you contribute $200 for 10 years.
How to Calculate Investment Growth
Pick a compounding frequency, convert it to a monthly equivalent rate, then iterate month by month or use the closed-form future-value expressions above.
Compounding at 7% on $10,000 (no deposits)
More frequent compounding raises the effective yield slightly at the same nominal rate.
| Compounding | About |
|---|---|
| Annual | $19,672 |
| Monthly | $20,096 |
| Daily | $20,137 |
Fees and taxes
A 1% annual fee can erase a large share of a 7% assumption over decades. Taxable accounts also lose a slice to tax on distributions. Enter a net return if you want those effects in the sketch.
What this projection leaves out
Markets do not compound at a flat 7%. Sequence-of-returns risk, contribution skips, and employer matches all move the ending balance. This page also assumes deposits land at month-end and stay invested — it will not model a withdrawal year or a target-date glide path. If you need to solve for the payment that hits a future goal, switch to the finance calculator and solve for PMT with a negative present value (cash you invest) and a positive future value (the goal). Pair a nominal return here with the inflation calculator if you want a rough constant-dollar reading of the same dollars.
Frequently Asked Questions
Is the rate an APY?
You enter a nominal annual rate. Compounding frequency changes the effective yield.
Can I contribute annually?
This widget adds money monthly. For a yearly deposit, divide it by 12 as an approximation or use the finance calculator.
Does this model withdrawals?
No. It only accumulates.
What frequencies are allowed?
1, 2, 4, 12, or 365 periods per year.
Is this investment advice?
No. Markets do not return a constant rate.
Guides that use this calculator
- What Is Compound Interest? Formula and Examples
Compound interest grows a balance on a growing base. Here is the formula, a $1,000 example and how monthly deposits change the story.
- How Much Do I Need to Retire? Nest Egg and the 4% Rule
A retirement sketch is savings grown to a target age, then a 4% withdrawal test. Here is the math and what it leaves out.