401k Contribution Calculator

What is the 401k Contribution Calculator?

A 401(k) is an employer-sponsored retirement account, often with a company match — money your employer adds on top of what you contribute. This calculator projects your balance at retirement from your salary, contribution rate, the employer match and your expected investment return, and highlights how much of the result is free match money.

The formula

Your current balance and each year's total contribution both compound to retirement:

FV = B(1 + r)ⁿ + C · ((1 + r)ⁿ − 1) ÷ r

B

current 401(k) balance

C

annual contribution = your amount + employer match

Employer match

salary × min(your %, match limit) × match rate

r, n

annual return, and years to retirement

The match is the highest-return money in the whole calculation — it's an instant gain before any market growth.

Worked example

On a $70,000 salary, contributing 6% with a 50% match up to 6% of salary, starting from a $20,000 balance, at a 7% return for 30 years.

You add $4,200 a year and your employer adds $2,100 — $6,300 total. After 30 years the account is projected to reach $747,348, with $63,000 of that coming from the match before growth.

Prefer your own numbers? Enter them in the calculator above — it recomputes instantly.

Key terms

Employer match

Money your employer contributes based on what you put in — effectively free money.

Match limit

The cap on how much of your salary the employer will match, e.g. up to 6%.

Vesting

How long you must stay before employer contributions are fully yours to keep.

Expected return

The average annual growth you assume for the account's investments.

Frequently asked questions