The Miami Dolphins in 2019 had an average age on their opening 53-man roster of 25.2. The team was almost a full year younger than the average age of all the rosters in the league. Miami was tearing down their roster that season, looking to rebuild into a contender over the following few years.
In 2020, the team was up to 25.4 years old on average, 30th in the league in terms of age. Only the New York Jets and Jacksonville Jaguars were younger, according to Spotrac.
Last year, the Dolphins averaged 25.