IELTS Academic or Duolingo English Test: how do they compare?

Many students and institutions have questions about the differences between Duolingo English Test (DET) and IELTS Academic for academic study. Research carried out by experts at Georgia State University shows that there are big differences between the two tests in terms of their suitability for recruiting students for higher education courses.

Read the full research report

Here is a quick recap of the findings, which will help you discover how the two tests compare and what it means for you.

IELTS Academic is a more complete test of the skills students need in higher education

DET does not cover all of the key language skills needed for academic success because it concentrates
on vocabulary and grammar, while IELTS Academic covers a much wider range of communicative skills
across all four language skills – listening, reading, writing and speaking.

See the skills covered by the two tests

The materials and topics in IELTS are more academically oriented

IELTS Academic focuses on authentic academic content and interactions, ensuring every test is fit for purpose and relevant for what a test taker needs once they get to university.

The test materials in DET are written in a more familiar way and do not focus on academic language, which means DET may have limitations for higher education institutions in terms of predicting academic success.

See the contextual differences of the two tests

Test scores should be compared with caution

The research findings remind us that it is difficult to make score comparisons between two very different tests and institutions should not just rely on simple conversion tables to understand what scores mean. Looking closely at what is tested is more informative to ensure that test takers have the right language skills and confidence to follow an academic course successfully.

Find out more about how to compare test scores

IELTS Academic is more transparently aligned to the CEFR

The Common European Framework for Reference for Languages (CEFR) is an international standard for describing language ability. Different exams report results in relation to the CEFR but there are big differences in the way they do this.

IELTS scores are linked to the levels of the CEFR by research and validation studies carried out over many years, and this information is available on the IELTS website and in academic publications.

The researchers were unable to find any publicly available information about how DET maps its scores onto the CEFR and recommend that the CEFR levels provided by Duolingo are interpreted with caution.

Find out more about IELTS Academic and the CEFR

What does this mean for universities?

The key conclusion for you to take away is that DET test tasks are less academically oriented and heavily weighted towards vocabulary and grammar. A test that focuses on these skills can be useful for making rough distinctions between learners, but universities are recommended to be aware of the limitations of DET in terms of predicting academic success and to compare DET test scores with caution.

IELTS Academic covers vocabulary and grammar, but it also includes in depth assessment of communication skills and the ability to understand and use language in academic contexts. The face-to-face speaking test and the extensive writing paper mean that IELTS test scores reflect the ability to use the language required in the real world.