What this calculator does
This calculator shows the immediate raise you are giving up when you do not contribute enough to capture your full employer 401k match.
The math
Matched contribution = min(your contribution, employer match %). Employer match = matched contribution × employer match % × salary.
Worked example
With a $70,000 salary, 4% employer match, and only a 2% contribution, you leave about $1,400 of free employer money on the table each year.
Why this matters
Your salary and your spendable income are not the same number. This calculator shows what you actually keep and what that means for your budget.
Methodology and transparency
This page publishes the exact formula used to compute the result, so you can verify it in a spreadsheet or check the assumptions against your own situation. The worked example uses the tool default inputs; change any number and the result updates live in your browser. No data is sent or stored.
Common questions
Is a 401k match really free money?
Yes. It is part of your compensation that you only get if you contribute.
Should I pay off debt before getting the match?
Usually no. A 50% or 100% immediate match almost always beats high-interest debt.
What if my employer match is complicated?
Enter the percentage of your salary your employer matches. Some plans tier the match, so run the calculation for your tier.