401(k) Calculator
A 401(k) grows from three things working together: what you put in, what your employer adds, and years of compounding. Slide your salary, contribution rate, match, and return to project your future balance. Pay special attention to how much the match contributes on its own.
How this math works
Your contribution is a percent of your salary set aside each year, and the employer match adds a percent of what you contribute up to a cap stated as a percent of salary. We add both streams every month and let the balance compound at your chosen return until retirement.
The employer match is the closest thing to free money in personal finance, since it is extra pay you only receive by contributing. Contributing at least enough to capture the full match is almost always the highest-return move available to you.
Common questions
How does the employer match work?
Your employer adds a percent of what you contribute, up to a cap measured against your salary. A common setup is 50 percent of your contributions up to 6 percent of salary, which we use as the default.
Why should I get the full match?
The match is additional compensation you earn only by contributing, so leaving it on the table is leaving guaranteed money behind. It is usually the first goal before any other investing.
Is the projected return guaranteed?
No. The annual return you set is an assumption, and real markets rise and fall year to year. Use the projection as a planning guide, not a promise.
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