401(k) Calculator

401(k) Calculator for educational purposes.

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401(k) Calculator: Complete 2026 Guide

Your 401(k) is likely your largest retirement savings vehicle — and the difference between contributing 6% versus 15% of salary can mean $500,000+ more at retirement. This calculator models growth with your specific employer match, contribution rate, and investment allocation.

Our free 401(k) Calculator helps you estimate costs based on 9 key financial variables. The calculator provides 4 detailed outputs based on current rates and financial benchmarks.

Enter your details to get estimates based on current financial data as of 2026.

What you'll learn:

  • Accurate 401(k) calculator estimates based on your specific inputs
  • Low, average, and high cost ranges for budgeting
  • How local factors impact pricing
  • Strategies for maximizing your financial outcome

401(k) Calculator Cost Breakdown

Understanding the cost breakdown helps you budget effectively for your 401(k) calculator project. Here are the typical cost components:

How to Calculate 401(k) Calculator

Our 401(k) calculator uses a multi-variable formula that accounts for the following inputs:

  1. Scenario Complexity — Choose from: Basic / Standard, Typical, Advanced / Complex
  2. Current Age — Range: 18 to 80
  3. Retirement Age — Range: 50 to 80
  4. Annual Salary ($) — Range: 10,000 to 1,000,000
  5. Contribution (%) — 2026 max: $24,500 ($32,500 if 50+)
  6. Employer Match (%) — Employer match percentage
  7. Match Limit (% of salary) — Range: 0 to 20
  8. Current Balance ($) — Range: 0 to 10,000,000
  9. Expected Annual Return (%) — Range: 0 to 15

Based on your inputs, the calculator provides:

  • Projected Balance at Retirement — Dollar amount based on current market rates
  • Total Contributions — Dollar amount based on current market rates
  • Employer Contributions — Dollar amount based on current market rates
  • Est. Monthly Retirement Income — Dollar amount based on current market rates

All calculations incorporate location-specific cost adjustments when a ZIP code is provided, using data from industry databases updated for 2026.

Our 401(k) Calculator Methodology

Projects 401(k) balance growth over time by modeling employee contributions, employer matching (various formulas), vesting schedules, investment returns across asset allocations, and the tax advantage of pre-tax vs. Roth contributions. Compares outcomes at different contribution rates.

Data Sources:

  • IRS Publication 560 for 401(k) contribution limits and catch-up provisions
  • Vanguard How America Saves report for average employer match rates and participant behavior
  • Bureau of Labor Statistics National Compensation Survey for employer match prevalence and formulas

Key Assumptions:

  • 2026 contribution limits: $23,500 employee (under 50), $31,000 with catch-up (50-59, 64+), $34,750 super catch-up (60-63)
  • Most common employer match: 50% of first 6% of salary (effectively 3% free money)
  • Default investment return assumption: 7% real (10% nominal minus 3% inflation) for diversified stock/bond portfolio
Accuracy: Actual 401(k) growth depends on market performance, fund selection (index vs. active), expense ratios, and consistency of contributions. This calculator uses long-term average returns — actual year-to-year returns will vary significantly. The most important factor is contribution rate — increasing from 6% to 15% of salary can double your retirement balance.

Factors That Affect 401(k) Calculator Costs

Several factors influence your 401(k) calculator estimate:

Scenario Complexity
Ranges from "Basic / Standard" to "Advanced / Complex." Choosing Advanced / Complex can cost 1.5x more than Basic / Standard.
Current Age
A key variable in determining your 401(k) calculator estimate.
Retirement Age
A key variable in determining your 401(k) calculator estimate.
Annual Salary ($)
A key variable in determining your 401(k) calculator estimate.
Contribution (%)
2026 max: $24,500 ($32,500 if 50+)
Employer Match (%)
Employer match percentage
Match Limit (% of salary)
A key variable in determining your 401(k) calculator estimate.
Current Balance ($)
A key variable in determining your 401(k) calculator estimate.
Expected Annual Return (%)
A key variable in determining your 401(k) calculator estimate.
Market Conditions
Interest rates, inflation, and economic indicators fluctuate over time and directly affect your results. Federal Reserve policy changes can shift rates within weeks.
Time Horizon
Longer time horizons amplify the effect of compound interest and rate changes. Even small rate differences compound into significant dollar amounts over years.

Understanding Your 401(k) Calculator Results

After you run the calculator, your results include interactive sections that help you make informed decisions:

Financial Breakdown

Your results separate principal from interest (or contributions from earnings) so you can see exactly how your money is working. Understanding this split helps you evaluate whether refinancing, extra payments, or alternative strategies could save you money over time.

Visual Chart

Charts make it easy to grasp the relationship between what you pay and what you owe (or what you save and what you earn). A quick look at the visual split helps you decide whether your current approach is on track or whether adjustments to your payment or contribution strategy could improve your outcome.

Payment or Growth Schedule

The schedule shows how your balance changes period by period — whether that is a loan being paid down or savings growing over time. Each row shows the split between principal and interest (or contributions and earnings), so you can see exactly when you cross key milestones. This long-range view helps you plan major financial decisions with confidence rather than guesswork.

Save and Share Your Results

Download your complete results as a CSV spreadsheet or PDF report. The PDF includes all your inputs, key results, and schedule data — ready to share with lenders, financial advisors, or anyone else who needs to review the numbers. No account or signup required.

How to Save Money on 401(k) Calculator

Here are proven strategies to reduce your costs:

  1. Compare Rates from Multiple Lenders: Shop rates from at least 3 lenders. Even a 0.25% difference in interest rate can save thousands over time.
  2. Automate Your Savings: Set up automatic transfers to savings or investment accounts. Consistent contributions compound significantly over time.
  3. Maximize Tax-Advantaged Accounts: Contribute to 401(k) up to employer match, then fund IRA/Roth IRA. Tax-advantaged growth accelerates your returns.
  4. Reduce High-Interest Debt First: Pay off credit cards and high-APR loans before investing. Eliminating 18-25% APR debt is a guaranteed return.
  5. Review Fees and Expense Ratios: High fund fees erode returns. Index funds with 0.03-0.10% expense ratios outperform most actively managed funds over time.
  6. Use Balance Transfer Offers Strategically: 0% APR balance transfer offers can save hundreds in interest — but pay off before the promotional period ends.

401(k) Calculator FAQs

At minimum, contribute enough to get your full employer match — that is free money (typically 3-6% of salary). Financial advisors recommend saving 15% of gross income for retirement including the match. The 2025 contribution limit is $23,500 ($31,000 for age 50+). Starting early matters enormously: $500/month from age 25 at 7% return grows to $1.2M by 65. The same amount from 35 reaches only $567,000.
Choose Roth if you expect a higher tax bracket in retirement (younger workers, rising income). Choose traditional if you are in a high bracket now and expect lower income later. A common strategy: split contributions between both for tax diversification. Your employer match always goes into the traditional pre-tax bucket regardless of your election. If unsure, Roth is generally better for those under 40.
At minimum, contribute enough to get the full employer match — anything less is leaving free money on the table. Financial advisors generally recommend saving 15% of gross income for retirement (including employer match). If starting late, aim for 20-25%. Contribution priority: (1) 401(k) up to employer match, (2) Max Roth IRA ($7,000/$8,000 with catch-up), (3) Max remaining 401(k) to $23,500/$31,000, (4) HSA if eligible, (5) Taxable brokerage account.
Choose traditional (pre-tax) if your current marginal tax rate is higher than your expected retirement rate — you get the tax break now when it is worth more. Choose Roth if your current rate is low (early career, lower income year) or you expect rates to rise. A common strategy: split contributions 50/50 to hedge against tax rate uncertainty, then adjust based on your annual tax situation. High earners (>$200K) generally benefit more from traditional due to current high marginal rates.
Our calculator uses current market rates and established financial formulas to provide estimates within typical industry accuracy. Results are based on the inputs you provide — actual outcomes depend on market conditions, fees, and individual circumstances. Use this as a planning tool alongside professional financial advice.
You'll enter key financial variables such as amounts, interest rates, time periods, and contribution levels. Each input includes guidance text to help you choose realistic values. The calculator adjusts results instantly as you change any variable.
Our financial calculator data is updated monthly using Federal Reserve rates, BLS economic indicators, and IRS contribution limits. Market-dependent calculations (mortgage rates, savings yields) reflect current published benchmarks.
Our estimates provide a useful starting point for financial planning, but they should not be used as tax advice. Tax situations vary by individual. Consult a tax professional or CPA for personalized guidance.
contribution amount, employer match formula (e.g., 50% match on first 6%), investment selection (target-date funds, index funds), expense ratios, vesting schedule, and current tax bracket. Getting an accurate estimate requires considering all these variables for your specific situation.
Yes — the calculator is completely free with no signup required. You can run unlimited calculations, download results as CSV or PDF, and share them with your financial advisor.

Why Trust Our Calculator?

Based on current market rates
Federal Reserve and IRS data integrated
Location-adjusted cost-of-living factors
No signup or payment required
Updated monthly with latest data
Sources: Federal Reserve, BLS, IRS
CostSignals Finance TeamVerified Data

Financial Analysts

Data from Federal Reserve, FRED, and verified financial institution rates.

Updated monthly

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2026 max: $24,500 ($32,500 if 50+)

Employer match percentage

This calculator provides estimates for informational purposes only and does not constitute financial advice. Consult a qualified financial professional before making financial decisions.

All figures shown are estimates based on average costs and may vary significantly based on your specific situation, contractor, materials, and local conditions.

Past results do not guarantee future outcomes. Individual results may vary significantly.

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