Retirement Runway
Calculator

How to Calculate Your Retirement Runway

Step 1: Enter Your Corpus and Age

Enter your total retirement savings (corpus), retirement start age, and the age you want to plan until (typically 90–95 for safety).

Step 2: Set Monthly Spending

Enter your expected monthly retirement expenses in today's dollars. The calculator will adjust this for inflation each year automatically.

Step 3: Add Income Sources

Enter any additional monthly income you'll receive: Social Security, private pension, rental income, or part-time work. These offset your corpus withdrawals and extend your runway significantly.

Step 4: Set Returns and Inflation

Enter the expected annual return on your remaining portfolio and the inflation rate. Conservative estimates (5–6% return, 3% inflation) are recommended for retirement planning.

Step 5: Calculate and Review

Click "Check My Retirement Runway" to see how long your money lasts, the exact depletion age, sustainability verdict, and year-by-year schedule.

Understanding Retirement Runway Planning

What is a Retirement Runway?

Your retirement runway is the number of years your savings can sustain your lifestyle. It depends on four key factors: corpus size, spending rate, investment returns, and inflation. Additional income sources like Social Security extend the runway.

The 4% Rule and the 25x Guideline

The 4% rule suggests withdrawing 4% of your portfolio in year one, adjusting for inflation annually. This implies you need 25 times your annual expenses saved. If you spend $48,000/year, you need $1.2 million. This has historically sustained portfolios for 30+ years.

Why Additional Income Sources Matter

Every dollar of guaranteed income (Social Security, pension) is a dollar you don't withdraw from savings. If you spend $4,000/month and receive $1,500 from Social Security, you only withdraw $2,500 — reducing your withdrawal rate by nearly 40% and dramatically extending your runway.

The Inflation Problem

At 3% inflation, $4,000/month today becomes $7,200/month in 20 years. If your spending isn't inflation-adjusted, your lifestyle degrades. If it is, your corpus depletes faster. Planning for inflation is non-negotiable.

Healthcare Costs in Retirement

Healthcare is often the largest unexpected retirement expense. Medical costs typically rise 5–7% annually — faster than general inflation. Include a healthcare buffer in your monthly spending estimate, or plan separately.

Tips for Extending Your Retirement Runway

Delay Social Security if Possible

In the US, delaying Social Security from 62 to 70 can increase your monthly benefit by up to 77%. This permanently higher income stream significantly extends your runway.

Keep a Portion in Growth Assets

Don't move everything to bonds at retirement. A 60/40 or 50/50 stock/bond mix provides growth to offset inflation while managing volatility.

Use Dynamic Withdrawal Strategies

Instead of withdrawing a fixed inflation-adjusted amount, consider reducing withdrawals by 10–15% during market downturns. This flexibility can add years to your runway.

Build a 2-Year Cash Buffer

Keep 24 months of expenses in cash or short-term bonds. This prevents selling investments during market drops — the biggest destroyer of retirement portfolios.

Consider Part-Time Income Early On

Even modest part-time income ($1,000–$2,000/month) in the first 5–10 years of retirement can dramatically extend your corpus life by reducing early withdrawals when compounding matters most.

Frequently Asked Questions

How long will my retirement savings last?

It depends on corpus size, spending, returns, inflation, and additional income. Our calculator gives a personalized timeline showing the exact age your money runs out — or confirms it lasts your lifetime.

What is the 4% rule?

Withdraw 4% of your portfolio in year one, then adjust for inflation annually. Research shows this has historically sustained portfolios for 30+ years across most market conditions.

How much do I need to retire?

A common guideline is 25x annual expenses (from the 4% rule). $50,000/year spending = $1.25 million needed. But additional income sources reduce this requirement significantly.

How does inflation affect retirement?

At 3% inflation, $50,000 in expenses today becomes $90,000 in 20 years. Plan for inflation-adjusted spending to maintain your lifestyle.

Should I include Social Security?

Absolutely. Social Security and pensions reduce corpus withdrawals, significantly extending your runway. Enter all guaranteed income sources for accurate results.

What is a safe withdrawal rate?

Traditionally 4%, though 3–3.5% is more conservative. Higher returns and additional income allow higher rates. Our calculator shows your specific rate and sustainability.

What about healthcare costs?

Healthcare costs typically rise 5–7% annually. Budget separately or include in your monthly spending estimate. Medicare coverage at 65 helps but doesn't cover everything.

What if my money runs out?

If the calculator shows depletion, consider: reducing spending, delaying retirement, increasing your corpus, adding income sources, or adjusting your investment allocation for higher returns.

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