[greenyoda]

Your tax estimate seems low. Remember that on top of federal tax, there's California income tax, which could hit 10% if you're single[1] (assuming most Google and Facebook employees are in California), plus real estate tax if you own a house. If you have significant income/gains from your investments, that could push you into a higher tax bracket.

Also, your monthly expenses could be significantly higher if you have children (larger home, food, clothing, education, etc.), which most people probably end up having at some point.

Also, does your 8% growth rate on the S&P 500 account for taxes and inflation? (Unless 100% of your savings are in a 401(K), you'll be paying tax.)

[1] http://www.tax-rates.org/California/income-tax

[krishanath]

S&P 500 actually returned 10% between 1988 and 2018. If you invested $10K in S&P 500 in 1988 it would be worth $205K today. If you use a compound interest calculator you can see this corresponds to 10% growth per year.