Retirement / employer plan projection

401(k) projection

Project a 401(k) from today’s balance to retirement, including salary growth, your deferral rate and the employer match. The match is priced explicitly, so it is obvious when a contribution rate is leaving free money behind.

Years to retire33Match capturedFull matchGrowth share72.8%

Projected balance

$2,284,995

At age 65, before any withdrawals

Your contributions

$418,592

Over 33 years of deferrals

Employer match

$156,972

50% up to 6.0% of salary

Monthly income at 4%

$7,617

36.3% of final salary

Balance milestones

Projected balance every five years, with the contributions and growth that produced it.

Age 65

Balance milestones
Age	Balance	Contributions that year	Growth that year
Age 32	$45,000	—	—
Age 37	$131,120	$11,762	$7,755
Age 42	$262,739	$13,635	$16,234
Age 47	$459,899	$15,807	$28,980
Age 52	$750,982	$18,324	$47,847
Age 57	$1,176,116	$21,243	$75,455
Age 62	$1,791,951	$24,626	$115,507
Age 65	$2,284,995	$26,910	$147,602

Growth overtakes contributions partway through — that crossover is where compounding starts doing the heavy lifting.

Balance trajectory

Compounded balance from today to retirement, contributions included.

Contributions vs growth

What you and your employer put in, against what the market added.

Canonical equations

The exact relationships implemented by this engine.

e = min(salary·c, limit) · the elective-deferral cap binds at high salaries

m·min(e, salary·cap) · 50% of the first 6% is the most common design

B ← (B + e + match)(1 + r) · contributions are assumed to land before growth

4% · B / 12 · the common safe-withdrawal starting point

Show model notation and computationOpen the symbolic form, the variable definitions, and the step-by-step derivation when you need the detail.

A clear path from inputs to results.

A 401(k) projection has three moving parts: what you defer, what your employer adds, and what the market does over the decades in between. The employer match is the only one that is a guaranteed return, which is why the contribution rate deserves more attention than the return assumption.

Step-by-step methodWorked exampleAssumptions explained

How to use

Enter your current salary and your expected annual salary growth.

Set your deferral rate as a percentage of salary.

Enter the employer match design: the match rate and the salary percentage it applies up to.

Add your current balance and your age, then set the retirement age.

Choose a long-run return assumption and check it against the sensitivity grid.

Confirm your deferral rate is at least the match cap — below it you are declining free money.

The formula

e_t = \min(s_t \cdot c,\ \text{limit}), \qquad m_t = \mu \cdot \min(e_t,\ s_t \cdot \kappa), \qquad B_{t+1} = (B_t + e_t + m_t)(1+r)

Reference: IRC §402(g) elective-deferral limit; typical safe-harbour match design (50% of the first 6%).

Worked example

$95,000 salary, 8% deferral, 50% match to 6% (default inputs)

Inputs

Salary $95,000 growing 3% a year; deferral 8%.
Employer matches 50% of contributions up to 6% of salary.
Current balance $45,000 at age 32, retiring at 65.
Expected return 7%; annual deferral limit $24,500 (2026).

Calculation path

1
Year-one deferral: 8% × 95,000 = $7,600.
2
Year-one match: 50% × min(7,600, 6% × 95,000 = 5,700) = $2,850.
3
Each year the balance grows by contributions plus match, then compounds at 7%.
4
Over 33 years your deferrals total about $418,600 and the match about $157,000.
5
Compounding turns that into roughly $2.28m, of which about $1.66m is investment growth.

Result

Projected balance $2.28m · your contributions $418,600 · employer match $157,000 · 4% income $7,617 a month.

Interpreting the result

Two-thirds of the final balance is growth, not contributions — which is the entire argument for starting early. The match is worth about 37% of your own contributions here, an immediate return no market can offer. Note the deferral limit: at higher salaries the cap binds and the match calculation stops scaling with the deferral rate.

Assumptions & limitations

Returns are constant at the assumed rate. Real markets deliver sequence risk, which matters most near retirement.

Salary grows at a constant rate; promotions and career breaks are not modelled.

The deferral limit is an input because it is indexed annually — enter the current year’s figure.

The match formula is the common 50%-of-first-6% design; safe-harbour and dollar-for-dollar plans differ.

No vesting schedule, loans, hardship withdrawals or Roth 401(k) treatment is modelled.

Frequently asked questions

How much should I contribute?

At minimum, enough to capture the full match — that is an immediate 50–100% return on the matched portion. Beyond that, 10–15% of salary including the match is the usual planning target for a comfortable retirement.

Does the annual limit include the match?

No. The elective-deferral limit applies to your contributions only; the employer match sits under a separate, much higher total annual additions limit.

How does the 4% rule work?

It is a planning heuristic: withdraw 4% of the balance in year one and increase with inflation. It is not a guarantee, and it was derived from US historical data. A 3.5% starting rate is safer for a 30-year retirement.

What does the match really cost me?

Nothing. It is additional compensation. Declining it is equivalent to taking a pay cut, which is why the badge flags the amount left on the table when the deferral rate is below the match cap.

What return should I assume?

A diversified equity-heavy portfolio has historically returned 6–8% nominal over long periods. Use 5% for conservatism on a long horizon, and lower it as you approach retirement and shift to bonds.

Should I use Roth or traditional contributions?

Compare your marginal rate now with your expected rate in retirement. If you are in a high bracket now and expect a lower one later, traditional wins on arithmetic; the opposite favours Roth.