At age 65, assuming 5% average annual return and 3% salary growth.
Includes $100,000 starting balance
Lasts indefinitely at this withdrawal.
An employer match is money your employer adds to your 401(k) based on what you put in yourself. Nearly every plan describes it with two numbers: how much the employer adds per dollar you contribute, and how far up your salary that offer extends. A formula written as "50% up to 6%" means the employer adds fifty cents for each dollar you contribute, and stops counting once your contributions reach 6% of your salary.
Take the example this calculator opens with. On a $100,000 salary, a 10% contribution is $10,000 a year. The plan matches only the first 6% of salary you contribute, which is $6,000. The employer adds 50% of that eligible $6,000 — $3,000. Your total for the year is $13,000: $10,000 from you and $3,000 from your employer, or 13% of your salary going into the account.
Notice what the limit does. Raising your contribution from 6% to 10% adds $4,000 of your own money but not a single extra dollar of match, because the employer's obligation was already fully met at 6%. That asymmetry is why the calculator reports your contribution and the employer's contribution as two separate figures instead of one combined number.
This is the most common misreading of a benefits summary, and it can distort a retirement plan by hundreds of thousands of dollars. The percentage in a match rate is measured against your eligible contribution, not against your pay. A 50% match does not mean half your salary, half your total contribution, or half of anything you might expect at first glance — it means fifty cents per eligible dollar.
The practical ceiling is easy to compute: multiply the match rate by the salary limit. A 50% match capped at 6% of salary can never contribute more than 3% of your salary in a year. A 100% match capped at 4% can never contribute more than 4%. On a $100,000 salary those ceilings are $3,000 and $4,000 respectively — real money that compounds for decades, but nothing close to the figures people picture when they read "50%".
A second subtlety: you only reach the ceiling if you actually contribute enough. Someone contributing 3% of salary to a plan that matches 50% up to 6% receives 1.5% of salary, not 3%. The calculator flags this case directly, telling you when your own contribution rate sits below the level your plan is willing to match.
The presets in the calculator are hypothetical illustrations of formulas that appear frequently in plan documents. On a $100,000 salary with a contribution at or above each limit, they produce very different employer contributions:
The first and third formulas cost the employer the same 3% of salary, but they ask different things of you: one requires a 3% contribution to capture the full match, the other requires 6%. Real plans also use tiered formulas, non-elective contributions, or profit-sharing on top of a match, so treat these four as starting points rather than a catalogue. Your summary plan description is the authoritative source.
Salary is not decoration in this calculator — it is the quantity the entire matching formula is defined against. The limit in "up to 6%" is 6% of salary, so without a salary figure there is no way to know how many of your dollars qualify. A tool that asks only for a contribution amount and a match percentage has to assume every dollar you contribute is matched, which overstates employer money for anyone contributing above their plan's limit.
Salary also sets the scale of everything downstream. Two people with identical percentages and identical returns but different salaries end up with proportionally different balances, different employer contributions, and different total savings rates. Anchoring the model to salary makes the projection legible: every figure on the page can be expressed both in dollars and as a percentage of what you earn.
When contributions are set as a percentage, a rising salary raises your contribution automatically. Starting from a hypothetical $100,000 salary growing 3% a year, pay is about $103,000 in year two, $106,090 in year three, and roughly $181,000 after twenty years. A steady 10% contribution therefore rises from $10,000 to about $18,100 over the same period without you ever changing your election.
The employer's contribution rises alongside it, still bounded by the same percentage of the larger salary. Under a 50% match up to 6%, the employer's 3% of salary is $3,000 in year one and about $5,400 in year twenty. Because the increases arrive gradually and each one compounds for the remaining years, salary growth has a disproportionate effect on the final balance compared with a one-time contribution increase.
Salary growth is an assumption, not a promise. Careers include flat years, industry downturns, sabbaticals, and moves that reduce pay. Running the projection with a lower growth rate — or zero — is a quick way to see how much of your projected balance depends on raises that have not happened yet.
Contributions above the matching limit are not wasted — they are simply unmatched. The money still enters the account, still receives the plan's tax treatment, and still compounds at whatever return your investments earn. What changes is the rate of return on the decision itself: dollars inside the matching range arrive with an immediate employer contribution attached, while dollars above it rely on investment growth alone.
The calculator surfaces this explicitly. Contribute 10% against a 6% limit and it will tell you that 6% is matched and the extra 4% is not, in plain language, as the numbers change. Whether that extra 4% belongs in a 401(k), another account, or somewhere else entirely depends on your tax situation, your other goals, and your plan's investment options — questions this tool does not attempt to answer for you.
Every projected balance on this page is made of exactly three ingredients, plus whatever you had saved when you started:
The chart stacks these in the same order so you can see the shape change over time. Early on, the balance is almost entirely contributions. Somewhere in the middle of a long horizon the growth layer overtakes the contribution layers and keeps widening, which is the visual signature of compounding. The three totals under the headline figure always reconcile to the projected balance, subject to rounding.
The projection runs one year at a time from your current age to your retirement age, and compounds monthly within each year.
This calculator does not apply IRS contribution limits, and it deliberately does not display a hard-coded figure. Employee deferral limits, age-based catch-up amounts, and the combined employer-plus-employee limit are adjusted periodically, and a number printed here would eventually become wrong. Your contribution rate is treated as an editable assumption, and it is your responsibility to confirm that the amount you model is permitted for your age and plan in the year you are planning for.
One related distinction matters for accuracy: employer contributions are not employee contributions. They fall under a separate, higher combined limit, and the calculator keeps the two totals separate throughout for exactly that reason.
Real 401(k) plans carry rules this model intentionally leaves out in order to stay understandable. It does not account for:
Your plan's summary plan description is the authoritative source for how your match actually works, and it is worth reading before making decisions based on any calculator.
Last updated: August 2026
This 401(k) calculator is provided for educational purposes only and does not constitute financial, investment, tax, or retirement planning advice. All results are estimates based on the assumptions you enter: investment returns are not guaranteed, salary growth is an assumption rather than a certainty, employer matching varies by plan, contribution limits and tax rules are not applied, and actual results may differ. Read our full disclaimer.
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