How to use the juvenile court age checker
The United States has no single national age line. Juvenile court jurisdiction is set state by state, and the boundary has moved repeatedly in the past decade. Most states now treat anyone under 18 at the time of the offense as a juvenile, while a small number still cut off at 17. The lower boundary varies even more: several states set a minimum age of 10 or so for delinquency jurisdiction and others set none at all by statute. That is why every age field on this page is editable.
Federal cases follow 18 U.S.C. 5031, which defines a juvenile as a person who has not turned 18 and treats an act committed before the 18th birthday as juvenile delinquency, with proceedings available until age 21. 18 U.S.C. 5032 allows transfer to adult prosecution for defendants 15 and older charged with specified violent or drug offenses. States run their own transfer, waiver and direct file rules.
Two constitutional limits apply regardless of forum: Roper v. Simmons, 543 U.S. 551 (2005) bars the death penalty for offenses committed under 18, and Miller v. Alabama, 567 U.S. 460 (2012) bars mandatory life without parole for those offenders. Ages reflect the position as of September 2026, and you should confirm your state statute. This checker is for reference only and is not legal advice. Consult a licensed attorney about your specific situation.
Frequently asked questions
Jurisdiction normally turns on the age at the time of the offense, though some states also limit how long juvenile court can keep the case as the person gets older.
It depends on the state. Some fix a statutory floor, others rely on common law capacity rules, so enter the figure that your jurisdiction uses.