Contributing to an employer-sponsored 401(k) plan is an effective way to save for retirement: You get significant tax advantages, the money is automatically taken from your paycheck before you have the chance to spend it and, often, companies offer a match, which is essentially free money.
Consistent contributions can even make you a millionaire. In fact, the number of Fidelity 401(k) accounts with a balance of $1 million or more recently hit a record of 168,000, up 41 percent from last year.
To give you an idea of how your retirement savings stack up against your peers, check out the average 401(k) balances in Fidelity accounts, as of the second quarter of 2018, broken down by age. The data was provided to CNBC Make It by Fidelity, the nation's largest retirement-plan provider: