401(k) Calculator
Project your 401(k) balance at retirement, including employer match.
- Author
- CentCompass
- Last Updated
- Reading Time
- 4 min read
Projected balance
$2,180,318.99
Your contributions
$420,000.00
Employer contributions
$105,000.00
Investment growth
$1,645,318.99
What is the 401(k) Calculator?
A 401(k) calculator projects your retirement balance from your own contributions, your employer's matching contributions, and investment growth over time, applying the 2026 IRS contribution limit. It shows how much of the eventual balance comes from you, how much is employer money, and how much is pure compounding — a breakdown that usually surprises people.
How the calculation works
Your annual contribution is capped at the IRS elective deferral limit, with a catch-up allowance if you are 50 or older. The employer match is calculated from your salary according to your plan's formula, commonly a percentage of your contribution up to a share of pay. Both amounts are invested each year and grow at your expected return until retirement. Because contributions are made pre-tax in a traditional 401(k), the full amount compounds without an annual tax drag.
The formula
Annual employee contribution = min(your contribution, $24,500), with the catch-up added if eligible. Employer match = min(your contribution rate, the match cap) × salary × the match rate. Each year's total is invested and grows as FV = contribution × (1 + r)^(years remaining), summed across all years and added to the growth on your existing balance. For 2026 the elective deferral limit is $24,500; those 50 and over may add $8,000 for $32,500 total; and under SECURE 2.0 those aged 60 to 63 may instead add $11,250, for $35,750.
Worked example
Starting at 30 with $10,000 saved, contributing $12,000 a year on a $100,000 salary with a 50%-up-to-6% employer match, and earning 7% a year, the balance can exceed $1,500,000 by 65. The employer match alone contributes $3,000 a year — about $105,000 across 35 years before any growth on it. Declining to contribute enough to earn that match would forfeit both the $105,000 and everything it would have compounded into, which is usually the single most expensive retirement mistake available.
Tips
- Always contribute at least enough to capture the full employer match — it is unmatched return.
- The 2026 deferral limit is $24,500, or $32,500 from age 50.
- Raise your contribution rate with each pay increase so it never feels like a cut.
- Check the vesting schedule before leaving a job — unvested employer money stays behind.
- Review the fund expense ratios inside your plan; they compound against you for decades.
Common mistakes
- Contributing below the match threshold and leaving employer money unclaimed.
- Front-loading contributions and hitting the annual cap early, which can stop the match in later months.
- Cashing out the balance when changing jobs instead of rolling it over.
- Leaving the default contribution rate untouched for years after being auto-enrolled.
- Ignoring the vesting schedule when timing a resignation.
Limitations
The projection assumes a constant rate of return, steady contributions, and an unchanging employer match formula. It does not model income tax on withdrawal, required minimum distributions, market volatility, plan fees, loans against the balance, or salary growth. Real balances depend heavily on when returns arrive, not merely on their average, and the 2026 limits shown are adjusted annually by the IRS.
Frequently asked questions
How much should I contribute?
At an absolute minimum, enough to capture the full employer match, since anything less leaves guaranteed compensation on the table. Many planners suggest working toward 10–15% of income including the match, increased gradually as pay rises.
What is employer matching?
It is money your employer adds based on what you contribute, commonly expressed as a percentage of your contribution up to a share of salary — for example 50% of contributions up to 6% of pay. It is part of your compensation, not a bonus.
What is the contribution limit?
For 2026 the employee elective deferral limit is $24,500. Those 50 and over may contribute an extra $8,000, reaching $32,500, and under SECURE 2.0 participants aged 60 to 63 may add $11,250 instead, for $35,750.
Roth vs Traditional 401(k)?
Traditional contributions are made pre-tax and withdrawals in retirement are taxed as income. Roth contributions are made after tax and qualified withdrawals are tax-free. The choice turns largely on whether you expect a higher tax rate now or in retirement.
Is the employer match taxed now?
No. Matching contributions go in pre-tax and grow tax-deferred in a traditional 401(k), becoming taxable only when withdrawn. Employer matches are not counted against your own elective deferral limit.
When can I withdraw without a penalty?
Generally from age 59½. Earlier withdrawals typically incur income tax plus a 10% penalty, though exceptions exist — including the rule permitting penalty-free withdrawals if you leave your employer in or after the year you turn 55.
What happens to my 401(k) when I change jobs?
You can usually leave it with the former plan, roll it into your new employer's plan, or roll it into an IRA. A direct rollover avoids tax and penalties; cashing out triggers both and permanently removes the balance from compounding.
What is a vesting schedule?
Vesting determines when employer contributions truly become yours. Your own contributions vest immediately, but matching money may vest gradually over several years, and leaving before you are fully vested forfeits the unvested portion.
What are required minimum distributions?
RMDs are mandatory annual withdrawals that must begin at the age set in current law, ensuring tax-deferred balances are eventually taxed. Missing one carries a significant penalty, so the timing matters as retirement approaches.
Can I borrow from my 401(k)?
Many plans permit loans against the balance, repaid with interest to your own account. The borrowed amount stops compounding while it is out, and an unpaid balance can be treated as a taxable distribution if you leave the employer.
How do plan fees affect the result?
Administrative charges and fund expense ratios reduce your effective return every year and therefore compound against you. Over a multi-decade horizon, a difference of a single percentage point can consume a substantial share of the final balance.
What is a 403(b) or 457(b)?
They are workplace retirement plans for public education and non-profit employees, and for state and local government employees, respectively. They share the same elective deferral limit as a 401(k) but differ in some withdrawal and catch-up rules.
Related calculators
Related guides
Sources
- IRS — Retirement topics — 401(k) and profit-sharing plan contribution limits
- IRS — Retirement topics — catch-up contributions
- U.S. Department of Labor — Types of Retirement Plans
How this page is produced
Editorial process. CentCompass is maintained independently, and this page is written and checked against the official publications listed above before it goes live. There is no separate editorial reviewer. This page was last checked on . See our editorial policy.
How the calculations work. Every result comes from a small, unit-tested calculation engine rather than a spreadsheet or a hardcoded table. Loans use the standard amortization formula, growth uses compound-interest math, income tax applies the federal progressive brackets, and payroll applies Social Security and Medicare rules. Our methodology sets out each one.
Where the figures come from. Tax brackets, standard deductions, FICA parameters, and contribution limits are stored once in a dated registry and read directly by the calculators — the same values appear in the text above, so the two can never drift apart. Each figure records its source, effective tax year, and review status on our data sources page.
Update policy. Regulatory figures are checked against their primary source when the IRS, SSA, or another authority publishes new values — typically each autumn for the following tax year — and again at the scheduled review date recorded for each dataset. Figures that have not been checked yet are marked as draft on the data sources page until that check is complete.
Educational purposes only — not financial, tax, or investment advice (disclaimer).