TOEFL vs IELTS vs Duolingo for US Universities: How to Choose

Why US universities ask for an English test

If English is not your first language — or you did not complete your prior degree in English — most US universities ask for proof of English proficiency. The three tests you will most often see accepted are the TOEFL iBT (from ETS), IELTS Academic (jointly owned by the British Council, IDP, and Cambridge University Press & Assessment), and the Duolingo English Test (DET). All three are widely used, but each school sets its own policy on which tests it accepts and what score it wants.

The most important rule comes first: there is no single "best" test. The right choice depends on which tests your target universities accept, the minimum score each program requires, how quickly you need results, and which format suits how you work. This guide gives you a way to decide — it does not rank the tests, and it does not list score cutoffs, because those change and vary by school.

Whatever you choose, always confirm the requirement on each university's own official international-admissions page before you register. A test another applicant used successfully may not be accepted by your program, or may need a different minimum.

Step 1: Check acceptance at YOUR universities first

Acceptance is the deciding factor, so start here — not with format or price. TOEFL and IELTS Academic are accepted by the large majority of US universities for admission. The Duolingo English Test is accepted by many US institutions too, but acceptance is not universal, and some programs (or specific graduate departments within a school) accept it only conditionally or not at all.

Make a short list of the exact programs you are applying to. For each one, open its official admissions or graduate-program page and read the English-proficiency requirement. Note three things: which tests are accepted, the minimum score, and whether that minimum differs for undergraduate versus graduate admission.

One detail that trips people up: for IELTS you almost always need IELTS Academic, not IELTS General Training, which is meant for migration and non-academic purposes. Confirm the version required on the program page.

• Accepted tests can differ between the undergraduate office and an individual graduate department at the same university.
• Minimum scores are set per program and can be higher for graduate or specific majors.
• The Duolingo score database lists institutions that accept the DET, but the university's own page is the authority — verify there.

Step 2: Compare format and how you test best

All three assess reading, writing, listening, and speaking, but the experience differs. The TOEFL iBT has four sections and is delivered on a computer at a test center or at home with live proctoring; ETS reports the total takes roughly two hours. IELTS Academic also covers four skills; its Speaking section is a live interview with an examiner (in person or on video), and it is offered on paper or computer depending on your location.

The Duolingo English Test is fully online and on demand — you take it at home on your own computer with a webcam, and it is computer-adaptive, meaning it adjusts question difficulty to your responses using Item Response Theory and finishes in about an hour. There is no live examiner; speaking and writing samples are recorded and graded afterward.

Think about which setting suits you. A live speaking interview (IELTS) rewards conversational fluency; a fully digital, adaptive test (DET) rewards comfort with computer-based tasks and a strict at-home environment; the TOEFL sits between, with integrated tasks that combine skills. None is "easier" — they simply test in different ways.

Step 3: Weigh cost, scheduling, and turnaround

Practical logistics often break a tie once you know all three tests are accepted. Fees, available dates, and how fast results arrive differ, and they change over time — so treat any figure you read elsewhere as a starting point and confirm the current amount on each test's official website.

As a general pattern: the Duolingo English Test is booked on demand and returns results quickly (Duolingo states results are typically available within about two days). The TOEFL iBT and IELTS run on scheduled test dates, and their score-reporting timelines are published on the ETS and IELTS sites. If you are close to an application deadline, turnaround and the next available slot can matter as much as the fee.

Also factor in score sending. Policies on how many score reports are included and what extra reports cost vary by test — check each official site — and note how long scores stay valid, since a test taken too early may expire before you enroll.

• Verify the current test fee on ets.org (TOEFL), ielts.org (IELTS), and englishtest.duolingo.com (DET) — do not rely on a figure from a third-party page.
• DET is on-demand; TOEFL and IELTS use scheduled dates — check availability near your deadline.
• Confirm score-sending rules and how long each score remains valid before you book.

Understand the scores before you register

Each test reports on its own scale, so a number that sounds high on one is not directly comparable to another. IELTS reports an overall band from 0 to 9 in half-bands, averaged from four skill bands. The Duolingo English Test reports on a 10–160 scale in 5-point increments, plus skill and integrated subscores.

The TOEFL iBT is in a scale transition: ETS has moved to a 1–6 section scale, and during a two-year transition period after January 2026 test-takers also receive a comparable overall score on the familiar 0–120 scale. Because this is changing, read the current ETS scoring page and check what scale your university's stated minimum refers to.

The practical takeaway: once you know which tests your programs accept, look up each program's required score on its own scale, and make sure you are comparing your target to the correct, current scale. Do not convert between tests informally — universities publish their own equivalences where they accept more than one test.

A simple way to decide

Put the steps together into one short process. First, list your programs and record which of the three tests each one accepts and the minimum score. If only one test is accepted everywhere on your list, your decision is made — take that one.

If more than one is accepted across your list, narrow by fit and logistics: choose the format you will perform best in (live interview vs. fully digital adaptive vs. TOEFL's integrated tasks), then check dates, turnaround, and cost against your earliest deadline. Give yourself time to prepare and, if needed, to retake before the deadline.

Finally, re-verify everything on official pages right before you book, because requirements and scales are updated. This is general guidance to help you choose — the university's official admissions page and each test's official site are always the final word.