Calculators
401(k) Contribution Optimizer
Calculate your 401(k) contribution, employer match, match left unclaimed, contribution limit room and tax saving.
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- Nothing uploaded
The tool
Enter your numbers below. Results update as you type, and nothing leaves your browser.
Everything you enter stays on your own machine. Nothing is sent to us or to anyone else, which you can confirm in your browser network tab.
What people use it for
- Choosing a contribution percentage
- Checking you get the full employer match
- Planning to max out a 401(k)
- Comparing job benefits
About this tool
What the 401(k) Contribution Optimizer does
An employer match is an instant return on your savings, so the first goal is usually to contribute at least enough to capture all of it. This optimiser shows your contribution and the employer’s, any match you are leaving behind, how close you are to the annual limit and the income tax a pre-tax contribution saves.
Formula
- Your contribution = salary × contribution % (capped at the limit)
- Match = min(your contribution, salary × match cap) × match rate
- Missed match = full available match − match received
Worked example
Using the starting values in the calculator above:
| Input | Value |
|---|---|
| Annual salary | $90,000 |
| Your contribution | 6% |
| Employer matches | 50% |
| Up to this share of salary | 6% |
| Annual employee limit | $24,500 |
| Catch-up contribution allowed | $0.00 |
| Marginal tax rate | 22% |
| Result | Value |
|---|---|
| Total going into the plan | $8,100 |
| Employer match left unclaimed | $0.00 |
| Your contribution | $5,400 |
| Employer match | $2,700 |
| Room under the limit | $19,100 |
| Contribution % to hit the limit | 27.2% |
| Income tax saved (pre-tax) | $1,188 |
How to read the result
Unclaimed match is a guaranteed return you are giving up. Raise your contribution to at least the match cap before other investing, if you can.
Some plans true up the match at year-end; without that, front-loading contributions can make you miss match in later pay periods.
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Questions
Questions about this tool
The things clients actually want to know — costs, timelines, ownership and what happens after launch.
The employer adds a percentage of what you contribute, up to a cap such as 6% of salary.
The IRS sets an annual employee limit, with an extra catch-up amount for people aged 50 and over. Check the current figures each year.
Often yes, if you can afford it, but compare with paying off high-interest debt and with IRA options.
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