The Duolingo English Test changed the game when it launched in 2016, making high-stakes English proficiency testing available on-demand, around the world. Since then, it has continued to evolve to meet the global need for innovative English language testing.

In the spirit of using the latest technologies in assessment, Duolingo annually updates the DET, introducing new features to better serve test takers and score users. When making these updates, we continually monitor the agreement rate between older and newer versions of the test, to ensure score comparability. 

Here’s a roundup of the updates and improvements we’ve made since 2020:

We refined test design, delivery, and scoring

Since 2020, we've refined our scoring models for both speaking and writing tasks and expanded our item bank with generative AI, enriching the diversity and range of test content. Our approach to creating a theoretical ecosystem prioritizes the test-taker experience, integrating it into our validity argument. Additionally, we've audited our test fairness review processes, and developed a bespoke quality assurance platform, showcasing our dedication to score consistency and reliability in digital-first assessments.

We've introduced innovative item types designed to more effectively measure academic English skills, reflecting real-world use and academic environments. These enhancements extend to our test's design, delivery, and scoring mechanisms, leveraging the latest in AI technology for more precise and reliable assessments. 

DET item additions since 2020

We’ve also revised the test’s concordance to match the growth the DET has experienced, as detailed in a recent Language Testing article, Practical considerations when building concordance between language tests.  These improvements ensure a robust evaluation of a test taker's ability to understand and use English in academic settings, setting a new benchmark in language assessment.

We enhanced security & proctoring 

We've continued to enhance the security and proctoring of the Duolingo English Test, focusing on foundational improvements such as detecting malicious software/hardware and advancing plagiarism detection. Our efforts extend to more sophisticated imposter/helper detection and innovative strategies against coordinated cheating efforts. 

We have embraced new technologies and enhanced our proctoring processes to safeguard test integrity, ensuring a fair testing environment for all participants. We've implemented a state-of-the-art ID verification system, ensuring the integrity of each test taker's identity, reinforcing our commitment to maintaining a secure and trustworthy testing environment. 

We've improved the test taker experience (TTX)!

To further improve the test-taking experience, we released new test readiness resources, including an updated mobile practice test, demonstrating our ongoing commitment to enhancing access and support for test takers around the globe.

To broaden accessibility, we've launched initiatives aimed at supporting test takers globally, including distributing free tests and providing additional resources. In 2023, we significantly expanded our Access Program, distributing over 48,000 free tests to increase educational opportunities.

These efforts reflect our commitment to making English language assessment more accessible, allowing a wider audience to prove their proficiency without the barriers traditionally associated with high-stakes testing.

Tests just keep getting better.

We aim to keep the DET at the forefront, ensuring it's both accessible and enjoyable. With a focus on innovation and delight, we're excited about bringing updates that improve the test, and the test taker experience!