Honestly, if you're 40 and haven't thought about how much in retirement savings you should actually have by now, you're not alone. Most people are way behind. But here's the thing -- knowing the actual benchmark can either stress you out or light a fire under you to take action.

Let's cut to it. The general rule floating around is that a typical 40-year-old in the US should have somewhere around $200,000 saved for retirement. That's the ballpark. But before you either panic or celebrate, understand that this number shifts based on your actual income. If you're making less than average, having $120,000 at 40 is solid. If you're a higher earner, you should probably aim closer to $300,000. It's all relative to the lifestyle you want to maintain later.

Here's a better way to think about it though. Forget the raw dollar amount for a second. The real benchmark is having between two and three times your current annual salary tucked away by 40. That's the number that actually matters because it scales to your situation.

So how do you get there if you're behind? The math is surprisingly simple. You should be saving about 15% of your salary for retirement. If you do that consistently from your working years, you'll have enough by your mid-60s to fully replace your employment income. The catch? Most people haven't been doing that. If you're already behind on how much in retirement savings you should have accumulated, you need to bump it up to 20% going forward. Yeah, it's tough with inflation eating everything right now, but those extra percentage points compound hard over time.

The good news is you've got 20+ years left to work with. That's a massive advantage. With that timeline, you can afford to take real risk. Stocks, specifically index funds like the S&P 500, should be your primary vehicle. Bonds have their place, but at 40 you need growth way more than safety. You'll likely see three or four bear markets between now and retirement anyway, so you've got time to recover.

What if you're 40 and have literally nothing saved? Sounds crazy, but it's not game over. Even dropping $5,000 a year into an S&P 500 index fund for the next 25 years gets you to roughly half a million in a tax-deferred account. That's real money.

The bottom line on how much in retirement by 40 is this: wherever you are right now, you can start moving the needle today. Even small moves compound into real momentum. The hardest part is just starting. Everything else is just discipline and time.