Around 55% of Americans say they're behind on saving for retirement, a recent Bankrate survey found.

In many ways, that makes sense. A comfortable retirement can seem like a hopeless goal when you look at commonly recommended savings guidelines. Financial firm Fidelityrecommends saving at least the equivalent of your salary by 30, three times your salary by 40, six times by 50, eight times by 60 and 10 times by 67.

But many Americans aren't meeting those milestones. Those between 25 and 34 have median 401(k) balances of just over $14,000, per a report by investment firm Vanguard.

That number doesn't include other types of investments or cash savings, but it's still nowhere near Fidelity's recommendation for people in their thirties. Those earning $15 an hour would need roughly $30,000 to meet the recommended goal.

If you're behind, it's OK. Here's why the stress of seemingly falling short doesn't have to be overwhelming, according to financial planners.

While a rule of thumb for savings goals can be helpful, it's not a one-size-fits-all plan for every type of saver, especially those just getting started.

There are many understandable reasons why someone may fall behind on saving for retirement, such as those still in school for a profession that will eventually pay well or those who only recently started their career. 

Continue reading at CNBC.