14 CFR 65.53: Eligibility requirements: General.

(a) To be eligible to take the aircraft dispatcher knowledge test, a person must be at least 21 years of age.

(b) To be eligible for an aircraft dispatcher certificate, a person must—

(1) Be at least 23 years of age;

(2) Be able to read, speak, write, and understand the English language;

(3) Pass the required knowledge test prescribed by § 65.55 of this part;

(4) Pass the required practical test prescribed by § 65.59 of this part; and

(5) Comply with the requirements of § 65.57 of this part.