For informational purposes only. Not financial, investment, or tax advice. Results are estimates based on the inputs provided. Consult a qualified financial professional before making financial decisions.
Calculator tool
How this calculator works
Use the explanation to understand the formula, assumptions, and practical limits behind the calculator result.
What the Calculator Projects
This calculator compounds your current retirement savings and future monthly contributions at the annual return you enter. The result is a planning projection, not a promise, because real markets do not deliver the same return every year.
How the Withdrawal Estimate Works
The tool converts the projected balance into a simple monthly estimate using a 4% annual withdrawal assumption:
Where:
- = monthly withdrawal estimate
- = projected retirement balance
The 4% figure is a common rule of thumb for first-pass planning. It is not a guarantee that a portfolio will last through every retirement length, inflation path, tax situation, or market sequence.
Inputs That Move the Result Most
| Input | Why it matters |
|---|---|
| Years until retirement | More time gives compounding longer to work |
| Monthly contribution | Raises the amount invested every year |
| Annual return | Small changes compound into large long-term differences |
| Current savings | Gives the projection a stronger starting base |
What This Estimate Leaves Out
The projection does not model taxes, fees, changing contribution rates, employer matches, inflation-adjusted spending, Social Security or pensions, withdrawals before retirement, or bad-return years near retirement. Use several scenarios rather than one optimistic return assumption.
Frequently asked questions
What does the 4% rule mean here?
The calculator uses it as a simple annual withdrawal estimate: 4% of the projected balance divided by 12. It is a planning shortcut, not a personalized retirement-income plan, and it does not replace analysis of taxes, inflation, portfolio mix, or sequence-of-returns risk.
Should I enter nominal or inflation-adjusted returns?
Use one system consistently. A nominal return produces future nominal dollars; a real, inflation-adjusted return produces values closer to today's purchasing power. Mixing a nominal return with today's spending needs can make the projection look stronger than it really is.
Which input should I test first?
Test contribution amount and years to retirement first because those are often the most controllable levers. Then test a more conservative return assumption to see how dependent the plan is on market performance.
Why can the real result differ so much from the projection?
Markets vary year to year, fees reduce net returns, inflation changes purchasing power, and withdrawals during downturns can damage a portfolio more than the same average return would suggest. The calculator shows a baseline, not a retirement guarantee.
