Jonathan Dayton was the youngest signer of the U.S. Constitution. He was 26 years old when he signed the document at the Constitutional Convention in Philadelphia on September 17, 1787.
Dayton represented New Jersey at the convention and later served in national politics. His age is a specific detail of the signing ceremony, which included delegates with widely different levels of experience and ages. The convention’s best-known senior figure, Benjamin Franklin, was 81 and was the oldest signer.
Dayton is sometimes confused with James Madison or Alexander Hamilton because both were younger, prominent constitutional supporters. Neither was the youngest signer: Madison was 36, while Hamilton was 30 when the Constitution was signed. The age record belongs to Dayton.
The Constitution was signed by 39 delegates, although 55 had participated in the convention. Dayton’s inclusion among the final signers highlights how the document brought together revolutionary veterans, established statesmen, and younger political leaders.