Calculator
Retirement Nest Egg Projection
All calculations run in your browser. No data is sent or stored.
Includes your contributions plus employer match.
S&P 500 historical avg ~10%. Conservative balanced portfolio ~6-7%.
Calculator uses constant return assumptions. Real-world returns vary year to year — this is an illustration, not a guarantee.
Adjust the sliders to project your retirement nest egg.
The math
How Compound Growth Works
The calculator uses the standard future value formula combining a present value lump sum with regular annual contributions:
Where PV = current savings, PMT = annual contribution, r = annual return, n = years to retirement. The "real" (inflation-adjusted) value uses FV / (1+i)n to express the future balance in today's purchasing power.
FAQ
Common Questions
What return rate should I use?
A common assumption is 6-8% for a diversified stock-and-bond portfolio. The S&P 500 has averaged ~10% nominal / ~7% real (after inflation) since 1926, but past performance doesn't guarantee future results. For conservative planning, use 5-6%; for aggressive planning, use 8-9%. Always be honest about your actual asset allocation.
Should I plan in nominal or real (inflation-adjusted) dollars?
Real dollars are more meaningful — they tell you what your nest egg will actually buy in today's terms. A $2M balance in 30 years sounds enormous, but at 2.5% inflation it's only worth about $950K in today's dollars. This calculator shows both so you can plan against real-world purchasing power.
How much do I need to retire?
A common rule of thumb is 25× your annual retirement expenses (the "4% rule"). If you'll need $60,000/year from savings, that's $1.5M. Add Social Security, pensions, and part-time income to reduce the burden on your portfolio. Try the Safe Withdrawal Rate calculator →
Why does starting early matter so much?
Because compound growth is exponential. $10,000 invested at 25 grows to ~$217,000 by 65 at 8% return. The same $10,000 invested at 45 grows to only ~$47,000. The first dollars saved have the most time to compound — they do the heaviest lifting in your portfolio.