Don't count on a dramatic reduction in Sam Bankman-Fried's time behind bars, even for good behavior.

Why it matters: After a judge slapped him with a 25-year sentence, it looks like the fallen entrepreneur will cross the age of 50 at least, before he is set free, legal experts tell Axios.

• That assumes the sentence isn't changed on appeal.
• "We are heartbroken and will continue to fight for our son." his parents, Alan Joseph Bankman and Barbara Fried, said in a statement published by The Daily Beast.

What they're saying: "Federal inmates generally have to serve 85% of their sentences by statute. There are a few programs that can reduce their sentence further, but I expect Bankman-Fried to spend approximately 20 years in federal prison," Neama Rahmani, president of West Coast Trial Lawyers, told Axios, via a spokesperson.

The basic reduction is 54 days per year of time served, which works out to about 3.7 years over 25 years.

• Plus, he might be able to count his time in the Metropolitan Detention Center toward his sentence.

Yes, but: There are other programs that can factor in, but — since they seem geared toward developing skills that can lower recidivism — they could be less applicable in this case.

In Thursday's sentencing, Judge Lewis Kaplan hinted at the (low) possibility SBF had learned his lesson, which could factor in any attempts to get less time.

• "There is a risk that this man will be in a position to do something very bad in the future, and it's not a trivial risk," Kaplan said as he neared rendering his sentence. "There is absolutely no doubt that Mr. Bankman-Fried's name right now is pretty much mud around the world, but one of the things he is is persistent."

The conditions of his sentence will be "nothing like a country club," Oleg Nekritin, an attorney in the defense practice at the Law Offices of Robert J. DeGroot, told Axios via a spokesperson.

• That is, if he lands at a medium-security prison. (Kaplan recommended medium or less to the Bureau of Prisons.)
• "He may be halfway-house eligible at around the 15-year mark of his sentence," Nekritin added.

The bottom line: The attorney says it is possible the sentence or the conviction could be changed on appeal, but that it all looks very unlikely.