401(k) Calculator

Use this calculator to project a 401(k) balance at retirement using employee contributions, employer match, and investment growth.

What this calculator does

The 401(k) calculator estimates how much a workplace retirement account could grow by retirement age. It combines current balance, salary-based contributions, employer contributions, and expected returns.

It uses:

• current age and retirement age
• current 401(k) balance
• annual salary and contribution rates
• expected annual return

401(k) Formula

FV = P(1 + r)^n + PMT × (((1 + r)^n - 1) / r)

Where:

• FV = future 401(k) balance
• P = current account balance
• PMT = monthly employee and employer contributions
• r = monthly return rate
• n = months until retirement

Example calculation

If:

• Current balance = 50,000
• Salary = 90,000
• Employee contribution = 10%
• Employer contribution = 4%

Then:

• Employee contribution = 9,000
• Employer contribution = 3,600
• Total annual contribution = 12,600
• Over 30 years at 7%, the balance grows substantially

The projected 401(k) balance can reach well over 1,000,000 with steady contributions.

What is a 401(k)?

A 401(k) is a US employer-sponsored retirement account. Employees contribute part of their salary, and many employers add matching or profit-sharing contributions.

Why 401(k) planning matters

• shows the long-term value of regular contributions
• highlights employer match impact
• helps compare contribution percentages
• supports retirement readiness planning

When to use this calculator

• setting a 401(k) contribution rate
• estimating retirement account growth
• valuing employer match
• comparing retirement ages

Common mistakes

• missing the full employer match
• ignoring contribution limits
• assuming returns are guaranteed
• not increasing contributions as salary grows

401(k) vs IRA

A 401(k) is sponsored by an employer and often includes matching contributions. An IRA is opened individually and has separate contribution limits.

Both can support retirement savings, but their rules and limits differ.

FAQs

What is a 401(k)?

A 401(k) is an employer-sponsored retirement account funded through payroll contributions.

How do you calculate a 401(k)?

Project current balance and annual contributions forward using compound growth.

What is a good 401(k) contribution?

A good starting point is enough to capture the full employer match, then more if your retirement target requires it.

What is the difference between a 401(k) and an IRA?

A 401(k) is workplace-based. An IRA is individually owned.