Most Duolingo English Test (DET) invalidations aren't about English ability at all — they're about equipment or room setup issues that were preventable. Here's the complete, practical checklist covering exactly what hardware you need and how to set up your testing space, in one place.
Table of Contents
- What Hardware You Actually Need
- Run the Official System Check First
- Room, Lighting, and Background Rules
- Audio and Silence Requirements
- Day-of Checklist
- FAQ
1. What Hardware You Actually Need
The DET does not require certified or specific-brand equipment. What you need is straightforward:
- A Mac or Windows computer (the test cannot be taken on a tablet, Chromebook, or in a browser alone — the DET desktop app is required)
- A working front-facing webcam and microphone — a built-in laptop camera and mic are generally sufficient if they're clear
- A smartphone for the mandatory secondary camera, positioned to show your screen and keyboard
- Speakers or headphones to hear audio prompts — check current official rules on which listening devices are permitted, since this has changed between test versions
- A stable internet connection for the full session
There's no meaningful advantage to buying a premium webcam or microphone for this test — clarity and reliability matter far more than specs. If your current hardware passes the official system check below, it's suitable.
2. Run the Official System Check First
Before test day, run Duolingo's official system check inside the DET platform. It verifies your internet speed, camera, microphone, speakers, app version, and secondary camera connection. Doing this one to two days ahead — not minutes before your session — gives you time to fix any issue without losing your test window.
3. Room, Lighting, and Background Rules
You'll need a private room where you can be alone for the full session. Beyond privacy, a few practical points reduce the risk of a flagged review:
- Lighting: Face a light source rather than sitting with your back to one — strong backlighting (like sitting in front of a window) can obscure your face on camera.
- Background: A plain, uncluttered background is safest. Avoid other people, screens, or reflective surfaces visible in frame.
- Camera positioning: Your face, hands, and keyboard should stay visible to the primary camera throughout. Your phone's secondary camera should be angled to show your full screen and keyboard, propped against something stable rather than held.
- Desk setup: Clear your desk of notes, books, and a second screen or device beyond your test computer and secondary-camera phone.
4. Audio and Silence Requirements
The test's audio monitoring listens for voices other than your own. Test in a room by yourself, let others in your home know not to interrupt you, and silence notifications on both your computer and your secondary-camera phone (Do Not Disturb is worth turning on for the phone specifically, since an incoming call could disrupt the secondary camera feed).
5. Day-of Checklist
- Government-issued photo ID ready (passport, driver's license, or national ID)
- One uninterrupted hour set aside, plus buffer time for setup and the room scan
- Every other application closed on your computer, including background processes (see Task Manager on Windows or the dock on Mac)
- Phone fully charged with Do Not Disturb enabled and positioned as your secondary camera
- Room cleared of notes, other devices, and other people
For the specific step-by-step secondary-camera and room-scan process itself, see our DET second camera rule guide. For the broader picture of what causes invalidations beyond hardware, see why DET results get invalidated.
6. FAQ
Do I need a special webcam or microphone for the DET?
No. A standard built-in laptop webcam and microphone are generally fine as long as they're clear and pass Duolingo's official system check.
Can I take the DET on a Chromebook or tablet?
No. The DET requires the desktop app on a Mac or Windows computer; it cannot be taken in a browser alone or on a Chromebook or tablet.
What if my internet connection isn't stable?
Run the official system check ahead of time to confirm your connection meets the requirement, and avoid testing on unstable public or shared networks if possible.