How to use the roth ira calculator
Prepare the values for this calculation
Project an account balance from a starting balance, contributions, an assumed return, and optional employer matching. Use the formula below to check that it answers your question. Read the input units before transferring figures from a statement, measurement or dataset.
Enter and check each input
- Starting balance: enter a value at least 0. Use the unit named in the label or selected above. Do not leave this required field blank.
- Monthly contribution: enter a value at least 0. Use the unit named in the label or selected above. Do not leave this required field blank.
- Assumed annual return (%): enter a value at least -99 and no more than 1000. Use the unit named in the label or selected above. Do not leave this required field blank.
- Years: enter a value at least 0 and no more than 100. Use the unit named in the label or selected above. Do not leave this required field blank.
- Employer match per contribution (%): enter a value at least 0 and no more than 100. Use the unit named in the label or selected above. Do not leave this required field blank.
- Employer match monthly cap (0 = no cap): enter a value at least 0. Use the unit named in the label or selected above. Do not leave this required field blank.
The input table gives a complete example. Keep units and time periods consistent across related fields.
Calculate and resolve any input error
Choose Calculate after entering the values. Changes also update the answer after a short pause. If an error appears, follow its message, correct the field and calculate again. Reset restores the example values.
Interpret the answer
Check Projected balance first. With the unchanged example inputs, it is $264,122.49. Compare the additional metrics with the primary result; each has its own label and unit.
Compare and keep a useful result
For a controlled comparison, keep every other example input unchanged and change Starting balance from 10000 to 11000. The resulting Projected balance is $267,432.70. This illustrates the equation’s response to that input, rather than a forecast of real events.
Read the chart’s axis labels and data table. A scenario curve changes one stated input while holding the others fixed; it does not add external observations. Use Download graph to save an available chart as a PNG.
Use Copy result or Download CSV to keep the answer. Share tool shares the page address without placing your input values in the URL. Recheck inputs and assumptions before using the result for a decision.
Roth IRA Calculator formula
Balance is compounded monthly while monthly contributions are added at period end.
Inputs and units
| Input | Format / range | Example |
|---|---|---|
| Starting balance | minimum 0 | 10000 |
| Monthly contribution | minimum 0 | 500 |
| Assumed annual return (%) | minimum -99; maximum 1000 | 6 |
| Years | minimum 0; maximum 100 | 20 |
| Employer match per contribution (%) | minimum 0; maximum 100 | 0 |
| Employer match monthly cap (0 = no cap) | minimum 0 | 0 |
Worked example
Using the example inputs above, the projected balance is $264,122.49.
- Projected balance
- $264,122.49
- Total contributions
- $120,000.00
- Modeled growth
- $134,122.49
- Monthly employer match
- $0.00
Results and assumptions
Projection only; actual investment returns, taxes, fees, contribution limits, and eligibility rules can differ.
Fix an input or unexpected result
Starting balance is required. Enter starting balance using the format and bounds in the input table. Zero and an empty field are different: use zero only if it is allowed and represents your data.
If your answer differs from the example, choose Reset and compare every field, including selected units and options. Check percentage versus decimal entry and whether values describe the same period. Round only the final displayed answer when reproducing the formula.
If a discrepancy remains, report the calculator issue with the page address, non-sensitive example inputs, actual result, expected result and a reference for your calculation.