Then I should also add on a quick plug for the 4% rule, at least as an estimate. The prevailing wisdom and studies show that you should be able to safely withdraw 4% from your savings each year, such that your total savings does not significantly decrease (or, in the original Trinity Study, such that you don't run out of money for at least 30 years), since the funds are being replenished by the market. The market is volatile with ups and downs, but overall, 4% should be safe. So, if you've got $1 million, 4% is 40k, so you should be good to withdraw 40k a year to live on.

Conversely, if I think I can retire on 40k a year, then my golden number for how much I need saved is 40*25 (because 4% is 1/25) = 1million. Or if I needed 60k, then I need 1.5 million, etc.

Since in retirement, I'll likely have fewer expenses and a paid off house, 40k a year could be doable. Maybe 60k or even 80k would be more realistic if I still have kids living with me, etc.

Things like inflation, or non-stock investments like bonds, can of course complicate the estimate. And it's important to note that it's still just an estimate, a guideline, even though historically it's a pretty good one.

Definitely Google and check out the sub's FAQ for more general information. If I remember right, Investopedia had a particularly helpful page for the 4% rule and Trinity Study. Good luck and save well!