The EF EPI is constructed each year from the results of a set of English tests completed by hundreds of thousands of adults around the world during the previous calendar year. In order to calculate a country’s EF EPI score, each test score was normalized to obtain a percentage correct for that test according to the total number of questions. All the scores for a country were then averaged across the different versions of the EF Standard English Test (EF SET), giving equal weight to each version.
The EF SET is a standardized, objectively-scored test of listening and reading skills that has been developed on a foundation of evidence-based research and ongoing psychometric analysis of test data. It is designed to classify test takers’ reading and listening performances on the test into one of the six levels established by the Common European Framework of Reference for Languages (CEFR). Two correlation studies confirm that EF SET scores are as reliable as traditional tests such as TOEFL and IELTS.
All adults 18 years old and above who have access to the Internet are eligible to participate in the EF EPI research by taking the EF Standard English Test (EF SET) at www.efset.org. This year’s global sample of 950,000 participants from 72 countries is balanced between male and female respondents and represents adult language learners from a broad range of ages. Female respondents comprised 46.3% of the overall sample, and the median age of adult respondents was 28 years. 98.9% of adult respondents were under the age of 60. Male respondents tended to be slightly older, with a median age two years higher than that of female respondents.
We recognize that the test-taking population represented in this index is self-selected and not guaranteed to be representative of the country as a whole. Only those people either wanting to learn English or curious about their English skills will participate in one of these tests. This could skew scores lower or higher than those of the general population.
In addition, because the tests are online, people without internet access or unused to online applications are automatically excluded. In countries where internet usage is low, we expect the impact of this exclusion to be the strongest. This sampling bias would tend to pull scores upward by excluding poorer, less educated, and less privileged people.
We are extremely interested in collaborating and supporting third party research, which we hope the EF EPI can contribute to. If you would like to consider collaboration, please contact us here. However, please note that we have not prepared the source data in such a way that can be shared outside the organization at this time.
The EF EPI should be cited as “EF English Proficiency Index” in the first mention, and “EF EPI” thereafter. The publisher is “EF Education First” in the first mention, and “EF” thereafter.
The EF EPI-c should be cited as “EF English Proficiency Index for Companies” in the first mention, and “EF EPI-c” thereafter. The publisher is also “EF Education First”.
We were only able to include countries with a minimum of 400 test takers. Unfortunately not all countries met this requirement, so many of the world’s countries were not included. We added several countries in this report compared to the previous edition, and we hope to be able to continue expanding in subsequent reports so that we can cover more and more parts of the world with this research.
The EF English Proficiency Index for Schools
The EF English Proficiency Index for Companies (EF EPI-c) is an evaluation of global workforce English skills.
Participate in the next EF EPI report by taking the EF SET – the world's first free standardized English test.