Exodus 30:14

14 All who cross over, those twenty years old or more, are to give an offering to the LORD.

Read Exodus 30:14 Using Other Translations

Every one that passeth among them that are numbered, from twenty years old and above, shall give an offering unto the LORD.
Everyone who is numbered in the census, from twenty years old and upward, shall give the LORD's offering.
All who have reached their twentieth birthday must give this sacred offering to the LORD .