401K Calculator

MCP Client Setup

Add the 401K Calculator MCP server to your MCP client configuration:

{
  "mcpServers": {
    "401k-calculator": {
      "command": "curl",
      "args": [
        "-X", "POST",
        "https://apistack.online/api/mcp/finance/401k-calculator/sse",
        "-H", "Content-Type: application/json",
        "-H", "Authorization: Bearer YOUR_API_KEY",
        "--data-raw", "@-"
      ],
      "transport": "sse"
    }
  }
}

Replace YOUR_API_KEY with your APIStack API key from the Dashboard.

Usage Examples

Example 1: Calculate 401K Growth with Employer Match

Calculate retirement balance with contributions and employer matching:

const result = await mcpClient.callTool('calculate_401k_growth', {
  currentBalance: 50000,
  annualContribution: 19500,
  currentAge: 35,
  retirementAge: 65,
  rateOfReturn: 7,
  employerMatch: 50,
  employerMatchCap: 6,
  annualSalary: 80000,
  includeCatchUp: false
});

// Returns detailed projection showing:
// - Estimated balance at retirement: ~$2.1M
// - Total personal contributions
// - Total employer match contributions
// - Investment gains breakdown
// - Year-by-year projection
// - Monthly retirement income estimates (4% rule)

Example 2: Plan Retirement Withdrawals

Analyze withdrawal sustainability and fund longevity:

const result = await mcpClient.callTool('plan_401k_withdrawals', {
  currentBalance: 1000000,
  annualWithdrawal: 50000,
  rateOfReturn: 5,
  withdrawalYears: 30
});

// Returns:
// - Years funded: How long money will last
// - Total withdrawn over the period
// - Remaining balance
// - Year-by-year withdrawal schedule
// - Fund exhaustion warning if applicable

Example 3: Calculate Required Minimum Distribution (RMD)

Calculate mandatory withdrawals for age 73+:

const result = await mcpClient.callTool('calculate_rmd', {
  currentBalance: 800000,
  currentAge: 73
});

// Returns:
// - Required minimum distribution amount
// - Distribution period from IRS table
// - Percentage of balance
// - Monthly distribution estimate
// - 10-year RMD projections

Example 4: Compare Contribution Scenarios

Compare current strategy vs maximum contributions:

const result = await mcpClient.callTool('compare_401k_scenarios', {
  currentBalance: 100000,
  annualContribution: 10000,
  currentAge: 40,
  retirementAge: 65,
  rateOfReturn: 7,
  employerMatch: 50,
  annualSalary: 75000
});

// Returns side-by-side comparison:
// - Current strategy final balance
// - Max contribution ($23K/year) final balance
// - Difference in retirement savings
// - Impact on retirement income
// - ROI on additional contributions

Key Features

• Growth Projections: Year-by-year balance projections with compound interest
• Employer Matching: Automatic calculation of employer match contributions
• Catch-up Contributions: Support for age 50+ additional contributions ($7,500/year)
• Withdrawal Planning: Analyze fund longevity with different withdrawal rates
• RMD Calculations: IRS-compliant Required Minimum Distributions for age 73+
• Scenario Comparison: Compare different contribution strategies
• IRS Limits: Built-in 2024 contribution limits and compliance checks

Parameters Reference

Age Requirements

• Current age: 18-100 years
• Retirement age: 50-100 years
• RMD calculations: 73+ years only

Contribution Limits (2024)

• Annual contribution: $23,000
• Catch-up (50+): $7,500
• Total combined limit: $69,000

Rate of Return

• Typical growth phase: 7-8%
• Typical retirement phase: 4-5%
• Range: -50% to 100%

Response Format

All tools return formatted text with:

• Account details and parameters
• Calculation results and projections
• Year-by-year breakdowns (where applicable)
• Retirement income estimates
• Actionable recommendations

Notes

• Calculations assume consistent annual returns
• Actual market returns vary year to year
• Does not account for inflation adjustments
• Tax implications not included
• Consult a financial advisor for personalized planning
• RMD calculations based on IRS Uniform Lifetime Table