Interactive tool

401k vs Roth IRA calculator

Most calculators compare Roth versus Traditional. This one compares 401k versus Roth IRA the way the question is actually asked, with the employer match modelled in.

Retirement Runway Calculator

Project your retirement balance

Quick scenarios
Annual employer match at current inputs
$2,250 free per year
Projected balance at age 65
A401k only, max contributions
Gross balance
$4,273,288
After tax retirement
$3,333,164
Pre tax growth, taxed on withdrawal
BRoth IRA only, no match
Gross balance
$1,138,928
After tax retirement
$1,138,928
Tax free growth, no employer match
CMatch plus max Roth IRA (recommended)
Gross balance
$2,392,276
After tax retirement
$2,116,539
Captures the match, adds tax free Roth
Match captured over career (Scenario C)
$417,783

Employer dollars compounded at 7%. Skip the match and this is the number you leave behind. Output uses 2026 IRS limits, including age based catch ups (50 plus) and the 60 to 63 super catch up.

How to read your results

What the three scenarios mean

Each scenario uses identical inputs (age, salary, raise, return, retirement age, retirement tax rate) and changes only what the contributions are.

Scenario A

401k only, max contributions

You fund the 401k up to the legal cap each year. The match is captured. There is no Roth IRA. Pre tax growth is taxed on withdrawal at the retirement rate you set.

Scenario B

Roth IRA only, no match

You fund only the Roth IRA. There is no 401k contribution and the match is left on the table. Growth and qualified withdrawals are tax free.

Scenario C

Match plus max Roth IRA

You contribute exactly the percentage needed to capture the full employer match in the 401k, then fully fund the Roth IRA. This is the recommended starting position.

Built in assumptions

What this calculator does and does not include

Included
  • 2026 IRS contribution limits (401k $24,500, Roth IRA $7,500)
  • Age based catch ups including the SECURE 2.0 super catch up
  • Employer match modelled as a percentage of contributions up to a salary cap
  • Annual raise compounded into salary, increasing absolute match dollars
  • Single retirement tax rate applied to pre tax balances at withdrawal
Not included
  • Inflation adjustments (use a real return such as 4 to 5 percent if you prefer)
  • State income taxes in retirement
  • Plan administration and fund fees, which vary by plan and custodian
  • Sequence of returns risk and market volatility
  • Future legislative changes to limits or tax rules
Plan ahead

Where each milestone falls on the runway

Retirement Runway
Key ages from career start to RMDs
Tax Year 2026
Career start
22
50
Catch up unlocks
Rule of 55 (401k)
55
59.5
59.5 penalty free
Super catch up (60 to 63)
60
65
Common retire age
401k RMDs begin
73
Frequently asked

Calculator questions

How accurate is a 401k vs Roth IRA calculator?+

Any retirement projection is an estimate. This calculator applies real 2026 IRS limits, age based catch ups, and a configurable rate of return, then projects compounded balances and applies your chosen retirement tax rate. Real outcomes depend on actual returns, fees, future limit changes, and personal circumstances.

What rate of return should I use?+

A 7 percent inflation adjusted return is a common default for diversified equity portfolios over multi decade periods. More conservative portfolios run lower (4 to 5 percent) and a 100 percent equity tilt may run higher. Stress test with 5 percent and 8 percent to see the range of plausible outcomes.

Why does the optimal scenario only put the match into the 401k?+

The optimal scenario is illustrative: capture every dollar of employer match in the 401k, then fully fund the Roth IRA. If you have additional savings beyond those two steps, route the rest back into the 401k toward the $24,500 employee cap. The result is a tax diversified mix.

Do you account for the SECURE 2.0 super catch up?+

Yes. The model uses age based 2026 IRS limits: $24,500 base, $32,500 at age 50 plus, and $35,750 for ages 60 to 63 under SECURE 2.0. Roth IRA limits step from $7,500 to $8,600 at age 50.