Well I'm 29 years old now. I currently invest about $4,320/year in mutual funds, max out my IRA every year, and put $3,600/year in my 401k. Once my salary continues going up I'll be able to do more but I'm still a young professional so I don't make 6 figures yet.
Correct me if I'm wrong, but you're investing $14,720/year ($4,320 in mutual funds, $5,000 IRA, $3,600 in 401(k) with $1,800 employer match).
At this rate, assuming you are starting at $0 (since you haven't mentioned your current net worth), you'd have just under $2 million by age 60 (assuming a 8% annual rate of return).
Note, however, that assuming inflation averages 3%, and you're currently 29, that $2 million will be worth $800,000 in today's dollars. At a 4% SWR, it would produce $32,000/year in income (in today's dollars). That's a very solid amount. Combined with even a modest Social Security entitlement, it should easily allow you to retire in comfort.
In order to reach $10 million instead of $2 million,
you'd need to be investing $6,250/month instead of your current $1,226.
On the other hand, that $10 million would produce a steady income of $160,000/year
in today's dollars, probably way more than you'll need.