How It Works - Retirement Scenario Planning Educational Toolkit

Methodology

How the retirement projection is calculated

Future value at retirement age

FV = P × (1 + r)ⁿ + C × [ (1 + r)ⁿ − 1 ] ÷ r

Balances and contributions are compounded at the assumed return rate r for n years. The second term is the future value of a level annual contribution stream.

Projection inputs mapped to the formula
Input	Symbol	What it represents
Starting balance	P	What you hold today before any new contributions.
Annual contribution	C	Amount added each year, including any employer match you enter.
Assumed annual return	r	Expressed as a decimal, so 6% is entered as 0.06.
Years to retirement	n	Retirement age minus current age.

Review the full list of assumptions and input definitions, or run your own figures in the contribution planner. Background on interpreting the results sits in educational notes.

Section 03 · Assumptions

Every number in the ledger traces back to this list

The planner applies one fixed set of inputs to each year of the projection. Change a row below and the entire schedule shifts.

Annual return6.0%: A constant nominal growth rate, compounded once per year. Markets do not move in even steps, so treat this as a smoothing device rather than a forecast.
Inflation2.5%: Applied to contributions and to the income goal, so the plan keeps pace with rising costs.
Time horizonWhole years: Measured from your current age to your retirement age. A longer time horizon generally gives each contribution more years to compound.
Contribution timingYear end: Contributions land at the close of each year and rise with inflation. Deposits made monthly would grow slightly more.
TaxesNot modeled: Neither contributions nor withdrawals carry a tax treatment here. Your bracket will change the take-home figure.
Fees0.0%: Fund expense ratios, advisory fees, and account charges are excluded. A 1% annual fee compounds against you over a long horizon.
Employer matchOptional: When enabled, the match adds up to 4% of salary per year. Vesting schedules and plan caps are not applied.
Salary growth0.0% real: Pay rises only with inflation unless you set a different rate in the scenario controls.
Retirement withdrawals4.0%: A guideline annual draw on the ending balance. Sequence-of-returns risk is not represented.
RoundingDisplay only: Calendar-year rows are rounded to the nearest dollar for readability; the underlying math stays unrounded.
Data handlingClient side: Calculations run in your browser. No account, no upload, and no personal data is collected or stored.

Educational tools only. Nothing here is financial advice, and results depend entirely on the assumptions you choose. See the educational notes for limits of use, or open the planner to test a different contribution rate.

Scope and limits

Educational notes

Illustration, not advice

Every balance you see is produced by the numbers you type. The planner does not know your tax bracket, your employer plan rules, or the rest of your balance sheet, so it cannot advise you. Take any figure you like to a licensed professional before you act on it.

Assumptions stay in view

Constant return, no taxes, no fees, and steady contributions. Those four choices drive the results, and each one is printed next to the numbers it touched rather than buried at the bottom of the page.

Nothing is stored or sent

The math runs in your browser. No account, no submission, no personal data leaves your device, which is also why the results reset the moment you close the tab.

Check the arithmetic yourself

Open the contribution planner and change one input at a time. If a number surprises you, walk back through the assumption tags until the change makes sense.