Estimated Class Sizes: More Than 90 National Universities

Updated September 24, 2017, to include revised honors class sizes.

Parents and prospective students are often interested in the average size of course sections. Assessing class size is extremely difficult because, first, a “class” has to be defined. Why is that difficult?

Some main sections (often in intro science, economics, business, etc.) may be very large, well in excess of 100 students, but the breakout labs and discussion sections are much smaller. Should  only the main section be counted, or should the labs and discussion sections also be included?

The best source for class size information and interesting data in general is the Common Data Set. Some universities publish their submissions, while others do not. The data in the CDS are used by U.S. News for many purposes, including the calculation of the percentage of classes with fewer than 20 students and the percentage of classes with more than 50 students. Using that information, we can also calculate the percentage of classes with enrollments between 2o and 50 students.

U.S. News does not include tutorials, thesis research, lab or discussion sections, and neither do we in our estimates of class sizes for honors programs. According to our counts, the average public university honors-only class section has 19.0 students. When we include honors credit classes that also have non-honors students, the overall average class size is 26.3 students. This is an important consideration, given that the tables below show that public universities have significantly larger class sizes.

The next level of difficulty when using U.S. News data is to plug in an average number for the three class size groupings. For the group of fewer than 20 students, we are using an average of 17.5 students per section; for the group of classes with 20-50 students, we are using an average of 35 students; and for the group of classes with more than 50 students, we are using an average of 110 students.

The first table below shows the overall average class size for 92 national universities, when all three class size groups are used with their corresponding percentages. The second table below shows the average class sizes of the same universities when the the group of more than 50 students is excluded. The reason: Anywhere from 75% to 91% of all classes have fewer than 50 students, so most of a student’s experience will not be in the large sections.

Average Class Size, including all classes (<20, 20-50, >50)

UniversityAvg All Classes
Chicago26.025
Duke26.725
Northwestern26.95
Columbia27.4
Tulane28.125
Tufts28.175
Yale28.625
Rice29.1
Harvard29.55
Georgetown29.575
Dartmouth29.8
Northeastern29.8
Johns Hopkins29.9
Caltech30.025
Vanderbilt30.2
NYU30.325
Brown30.6
Princeton30.65
Syracuse30.725
Penn30.775
Stanford31
Emory31.075
Boston College31.15
Brandeis31.65
Wash U31.7
Carnegie Mellon31.875
U of Miami31.9
Rochester31.925
Notre Dame32.35
Geo Washington32.525
BYU32.525
Boston Univ33.5
MIT33.775
Case Western33.9
Temple34.35
USC34.775
RPI34.9
Georgia34.925
Kansas35.375
Iowa35.825
Oklahoma35.9
UC Berkeley35.925
Virginia36.625
Connecticut37.15
Utah37.5
Colorado37.85
Florida38.425
Michigan38.875
Cornell38.875
Maryland39.125
North Carolina39.425
Arizona39.425
Penn State39.6
UC Irvine39.85
UCSB39.925
South Carolina40.175
Tennessee40.6
Delaware40.65
Missouri40.75
Nebraska40.925
Florida St41.225
Arizona State41.325
Massachusetts41.375
Auburn41.4
Purdue41.675
Kentucky41.75
Colorado St41.85
Wisconsin41.95
Stony Brook SUNY42.125
Indiana42.2
Illinois Chicago42.425
UCLA42.575
Illinois42.65
Oregon42.825
NC State42.85
Pitt43
Minnesota43.35
Rutgers New Bruns43.35
U at Buffalo SUNY43.7
LSU44.275
Washington St44.45
Virginia Tech45.1
Washington45.375
Oregon St45.675
Ohio State46.25
Georgia Tech46.925
UT Austin47.275
Iowa St47.575
Michigan State48.8
UC Davis49.125
Texas A&M50.65
UCSD55.35

Average Class Size, including only classes with <50 students

University% of All ClassesEst Avg Size
with <50 of Classes <50
Columbia9119.23
Yale9120.58
Harvard9020.61
Chicago9420.66
Northwestern9320.7
Princeton8920.84
Johns Hopkins9021
Stanford8921.24
Rochester8821.28
MIT8621.37
Duke9421.41
Brown9021.78
Penn9021.97
Tufts9322.02
Wash U8922.02
Rice9222.07
Caltech9122.12
Carnegie Mellon8922.22
Vanderbilt9122.31
UC Irvine8022.31
Case Western8722.53
Dartmouth9222.83
Northeastern9222.83
UC Berkeley8522.85
Syracuse9122.88
Tulane9422.9
Brandeis9022.94
Boston Univ8823.07
Michigan8223.26
Cornell8223.26
Emory9123.27
NYU9223.4
Georgetown9323.52
USC8723.53
UCLA7823.56
Virginia8523.68
Notre Dame9023.72
Geo Washington9023.92
BYU9023.92
Connecticut8524.29
UCSB8224.54
UCSD6424.61
RPI8824.66
Utah8524.71
Iowa8724.74
Florida8424.79
Wisconsin8024.94
U of Miami9225.11
Colorado8525.12
Stony Brook SUNY8025.16
Boston College9325.22
Massachusetts8125.28
Maryland8425.63
Illinois8025.81
Georgia Tech7525.9
Oregon8026.03
Kansas8926.15
Pitt8026.25
Arizona State8226.25
UT Austin7526.37
Missouri8326.57
Illinois Chicago8126.57
UC Davis7326.61
Purdue8226.68
Minnesota8026.69
Rutgers New Bruns8026.69
Oklahoma8926.74
Nebraska8326
LSU7926.78
South Carolina8426.88
Colorado St8226.89
North Carolina8526.97
Arizona8526.97
Washington St7927.03
U at Buffalo SUNY8027.13
Washington7827.15
Penn State8527.18
Indiana8227.32
Georgia9127.5
Temple9227.77
Iowa St7627.86
Florida St8428.13
Ohio State7828.27
Auburn8428.33
Delaware8528.41
Oregon St7928.58
Kentucky8428.75
Virginia Tech8028.88
NC State8329.1
Tennessee8629.3
Michigan State7629.47
Texas A&M7429.8