This is a list of universities in the United States classified among research universities in the Carnegie Classification of Institutions of Higher Education. This defines research institutions as those that spend more than $2.5 million on research and development", and assigns these institutions to one of three research designations based on total research expenditures and (for the higher two designations) production of research doctorates.
The 1994 edition of the Carnegie Classification defined Research I universities as those that:
The Carnegie Foundation reported that 59 institutions met these criteria in 1994.
In their interim 2000 edition of the classification, the Carnegie Foundation renamed the category to Doctoral/research universities-extensive in order to avoid the inference that the categories signify quality differences." The foundation replaced their single classification system with a multiple classification system in their 2005 comprehensive overhaul of the classification framework so that the term "Research I university" was no longer valid, though many universities continued to use it.
In 2015, the Carnegie Classification System reinstated the "Research I university" designations along with "Research II" and "Research III." The system in use from 2018, included the following three categories for doctoral universities:
In the 2018 classification, institutions were classified as either R1 or R2 if they "conferred at least 20 research/scholarship doctorates in 2016-17 and reported at least $5 million in total research expenditures." A "research activity index" was then calculated that included the following measures:
These four measures were combined using principal component analysis to create two indices of research activity, one representing an aggregate level of research activity and the other representing per-capita research activity. Institutions that were high on both indices were classified among "R1: Doctoral Universities â Very high research activity."
In the 2025 classification, all institutions with more than $2.5 million in research expenditure were classified into three "Research Activity Designations":
This revision also introduced a clear threshold for R1 classification, replacing the 10-metric score that had been used since 2005: (1) have $50 million in total annual research expenditures, and (2) grant 70 research doctorates per year. The threshold for R2 classification remained: (1) have $5 million in total annual research expenditures, and (2) grant 20 research doctorates per year. In both cases, the thresholds are taken as the higher of the most recent year or a three-year rolling average. Institutions that did not meet either the R1 or R2 thresholds but did have more than $2.5 million in research expenditure were classified as RCUs, without any requirement for awarding research doctorates. The titles for R1 and R2 were also changed, with the words "research activity" replaced by "research spending and doctorate production".
There are 187 institutions that are classified among "R1: Doctoral Universities â Very high research spending and doctorate production" in the Carnegie Classification of Institutions of Higher Education as of the 2025 update.
R1 universities spend at least $50 million a year on research and development and award at least 70 research doctorates.
Prior to the 2025 update, the R1 designation indicated that the university had a very high level of either aggregate research activity or per capita research activity (or both).
There are 140 institutions that are classified among "R2: Doctoral Universities â High research spending and doctorate production" in the Carnegie Classification of Institutions of Higher Education as of the 2025 update.
The R2 designation indicates that, on average, the university spends at least $5 million a year on research and development and awards at least 20 research doctorates.
Prior to the 2025 update, the R2 designation was assigned to universities with a high level of aggregate research activity or per capita research activity (or both), but not a very high level in either.
As of the 2025 update, the Carnegie Foundation classifies 216 institutions as "Research Colleges and Universities". This new category requires institutions spend at least $2.5 million on research & development and are not included in the R1 or R2 categories.