The EF English Proficiency Index (EF EPI) attempts to rank countries by the equity of English language skills amongst those adults who took the EF test. It is the product of EF Education First, an international education company, and draws its conclusions from data collected via English tests available for free over the internet. The index is an online survey first published in 2011based on test data from 1.7 million test-takers. The most recent edition was released on November 10th, 2020. using test data from (2.2) million test-takers in the year 2019.

The country had to have at least 400 test-takers The report consists of a country ranking table. The report is composed of a country ranking table, several pages of analysis with graphs correlating other economic and social factors with English proficiency, and an analysis of each region or continent. The 2020 report includes English proficiency levels by gender, age group, and region, within countries, and some English proficiency scores by city.

The website displays portions of the report and has an analysis of English skills in many countries and territories, GNI per capita and innovation all positively correlated with English proficiency, and English proficiency levels develop at different rates between countries, with only a few countries having English language skills At the lowest level, Europe as a whole has the highest level of English proficiency, while the Middle East scores the lowest, with women speaking English on average better than men.