From the article, Here are the median amounts of what individuals currently have saved for retirement, categorized by age:
Age Range Median Retirement Savings
Under 35 $18,880
35-44 $45,000
45-54 $115,000
55-64 $185,000
65-74 $200,000
75 or older $130,000
Source: Federal Reserve
What you actually need for a 25 year retirement varies a lot based on your location. From memory they said Miami, FL would review about $1.1m, while McAllen, TX would require about $570k.