The Duolingo English Test (DET) is an online, computer-adaptive English test taken at home. The official test process is about one hour: 5 minutes for setup and identity checks, 45 minutes for the scored assessment, and 10 minutes for writing and speaking samples. Certified results are normally available within 48 hours.
Before buying it, verify the exact programme and application route you will use. A university may accept DET for admission while a visa, professional regulator or scholarship applies a different English-test rule. Do not infer acceptance from a country-level claim.
Current DET format
- Setup and ID verification — 5 minutes: equipment, identity and security checks.
- Scored assessment — 45 minutes: adaptive reading, writing, listening and speaking tasks.
- Writing and speaking samples — 10 minutes: scored extended samples are recorded and shared with score recipients.
DET does not publish one fixed question count for every candidate. Its adaptive delivery selects items according to the evidence collected during the test, so candidates can receive different items and difficulty levels.
Current task families include short objective reading and listening work, dictation and highlighting, Interactive Reading and Interactive Listening, picture description, extended speaking and writing, Interactive Writing, and Interactive Speaking. Interactive Speaking is a 6-to-8-turn simulated conversation; Duolingo says each prompt allows 35 seconds and has no preparation time. The final samples are presented in a separate phase but are still scored and shared with institutions: the Writing Sample contributes to the overall, Writing, Literacy and Production scores, while the Speaking Sample contributes to the overall, Speaking, Conversation and Production scores.
How adaptive behaviour actually works
The DET changes item difficulty as it gathers evidence about proficiency. Duolingo says its Item Response Theory model accounts for both response performance and item difficulty so scores remain comparable even when candidates see different items.
That does not create an official “accuracy early matters more” rule. Duolingo does not say that one opening mistake caps the score, nor does it publish a special weighting for early questions. Treat every response as useful evidence: read the instruction, use the available time and answer independently.
Interactive Speaking is adaptive in a different way: follow-up prompts are selected from expert-reviewed material according to the content and quality of the preceding response. Prepare to answer the question asked and develop an idea naturally; do not memorise a monologue and force it into every turn.
Scoring and score interpretation
DET reports the overall score and all subscores from 10 to 160 in 5-point increments.
- Individual subscores: Reading, Writing, Listening and Speaking.
- Integrated subscores: Literacy (Reading + Writing), Comprehension (Reading + Listening), Conversation (Listening + Speaking) and Production (Writing + Speaking).
- Duolingo states that the overall score is the average of the four individual subscores, rounded to the nearest 5. Each integrated subscore is the average of its two component individual subscores.
There is no universal passing score and no defensible “competitive” score for all programmes. Use the minimum overall score and any subscore conditions published by each institution. Confirm that the requirement applies to your programme, intake and applicant type.
Certified DET scores are official results. A practice-test range or third-party estimate is only a preparation signal; it is not a certified score and an institution cannot verify it as one. Scores are valid for two years.
Price, results and retakes
The official purchase flow showed the current fee when this guide was verified. Because checkout pricing, taxes, bundles and faster-results options can change, check the total displayed in your DET account before payment rather than relying on an old converted amount.
Standard results are normally delivered within 48 hours. Duolingo also advertises a paid faster-results option with a 12-hour turnaround; verify its availability and current charge at checkout.
The official rules permit up to three test purchases in any rolling 30-day period. You must also wait for the result of one submitted test before starting another. A retake is a new official test, not a rescore of the previous session.
At-home security and proctoring
DET is not an unsupervised home quiz. The session is recorded and checked with AI-assisted monitoring and human proctor review before certification.
Current setup includes:
- a computer with camera, microphone, speakers and a supported connection;
- a smartphone used as a secondary camera;
- a room scan and an ear scan;
- a quiet, well-lit room with no other person present;
- both cameras positioned so required views remain visible;
- no headphones, earbuds, notes, outside assistance or other programs running.
Use Duolingo's current rules page as the authority. Looking away from the screen, another person entering, prohibited software or an incomplete camera view can breach the rules and prevent certification.
Preparation workflow
- Set the target. Record each programme's overall and subscore requirement. Separately verify any visa or regulator rule.
- Learn the current task families. Use the official readiness material and current practice test. Do not prepare from an old list that omits Interactive Writing or Interactive Speaking.
- Take a diagnostic practice test. Treat its range as an estimate, not an official DET score. Note weak skills and instruction errors.
- Build language evidence. Read varied prose, transcribe short audio, summarise spoken and written ideas, and practise clear timed speaking and writing.
- Practise interaction. For Interactive Writing and Speaking, answer the follow-up rather than repeating the first response.
- Rehearse the full environment. Complete at least one uninterrupted session on the same computer, network, phone stand, desk and room you plan to use.
- Book with margin. Leave time for certification, score sending and a permitted retake before the application deadline.
Readiness and booking checklist
- My exact programme confirms DET and states the required score.
- My visa, scholarship or professional route does not require a different test.
- My identity document and account details match.
- I checked the live checkout price and result option.
- My computer passes the official equipment check.
- My phone can serve as the secondary camera and remain powered.
- My room supports the room scan, ear scan and clear camera views.
- I can complete a full official practice test without instruction or setup surprises.
- My estimated practice range is at or above my target with a sensible buffer.
- My deadline leaves room for the normal 48-hour result process and score delivery.
Quick answers
How long is the DET?
About one hour: 5 minutes of setup, 45 minutes of scored assessment and 10 minutes of writing and speaking samples.
Is every candidate given the same number of questions?
No fixed count is published. The test is adaptive, so item selection can vary.
Does the first question matter more?
Duolingo publishes no special early-question weighting or “one mistake caps your score” rule.
What is the DET score scale?
Overall and subscores run from 10 to 160 in 5-point increments.
When are results available?
Normally within 48 hours. A paid 12-hour option may be available; check the live purchase flow.
Can I take DET at a test centre?
DET is designed as an online at-home test. It uses a computer plus a phone as a secondary camera.
How often can I buy and take it?
You may purchase up to three tests in any rolling 30-day period, and you must receive the result of one submitted test before starting another.
Is a practice score official?
No. A practice range is an estimate. Only a certified DET result is an official score.
