It’s actually in the Code of Federal Regulations – Title 34 Subtitle B Chapter VI Part 600 Subpart A § 600.2. As of 17 November 2025, a university credit hour is defined as one hour of classroom or direct faculty instruction and a minimum of two hours of out-of-class student work each week for approximately 15 weeks during one semester (45 = 3 x 15). For three credits, this totals 135 hours. Just something to keep in mind while choosing your next class or doing independent study.