Does Mercer Mettl Detect AI Tools? 2026 Proctoring Guide

Yes, and Mercer Mettl is the most invasive platform in this whole category. A fully configured Mettl assessment can require you to install the Mettl Secure Browser, which "shuts down all active applications, such as other browsers and cheating tools," blocks unauthorized websites and third-party software, and terminates your test outright if you share your screen after it starts. On top of that it captures your screen and camera "at every 60 seconds," runs audio analysis for background voices, and has a named flag for a phone in frame.

If the employer turned all of it on, a hidden AI tool on the test machine is not a risk you are managing, it is a risk you are ignoring.

Last checked: September 17, 2026. Every proctoring claim below links to Mercer Mettl's own documentation. We build InterviewMan, an AI interview assistant, so read the practical advice with that in mind.

Key takeaways:

Mettl's anti-cheating documentation lists 15 measures, including the Mettl Secure Browser, browsing tolerance with auto-termination, screen capture, video recording, audio proctoring, a mandatory 360-degree room check, IP restriction, copy-paste and print-screen blocking, and question randomization.

Screen Capture "captures the candidate's screen & Camera feed snapshots at every 60 seconds."

Visual proctoring flags are named and specific, including FACE_NOT_VISIBLE, ANOTHER_PERSON, AWAY_FROM_WINDOW, CANDIDATE_LOOKING_AWAY, CANDIDATE_FACE_PARTIALLY_VISIBLE, CANDIDATE_NOT_PRESENT, and MOBILE_PHONE_DETECTED.

Screen sharing is a hard stop. Per Mettl's candidate guide, "the test will terminate if the candidate shares a screen after starting MSB."

Proctoring comes in packages: AI only, AI plus secure browser and record-and-review, or live human proctoring where a Mettl employee watches you in real time and can interact immediately.

The second-device workaround that works on lighter platforms runs directly into MOBILE_PHONE_DETECTED and the 360-degree room check here.

What Mercer Mettl is and who uses it

Mercer Mettl is an assessment company owned by Mercer, and it sits across two markets at once: corporate hiring and academic or certification exams. That second market is why its proctoring is so much heavier than a developer-screening tool. When a platform also serves university finals and professional certification bodies, the feature list gets built for exam halls, not for a casual coding screen.

In hiring, Mettl is used widely for volume recruitment, campus drives, aptitude and psychometric batteries, and technical coding tests. Its remote proctoring product is marketed as an AI-based proctoring suite, sold alongside SecureProctor and the Mettl Secure Browser.

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The important structural fact for candidates: Mettl sells proctoring in tiers. A basic package authenticates you with email and password and proctors with AI alone. Higher packages add the secure browser and record-and-review, where a human reviews the recorded session at the points the AI flagged. The top tier is live remote proctoring, where a Mettl employee watches multiple test takers and can interrupt you.

What Mercer Mettl monitors

Mettl Secure Browser, if the employer requires it

MSB is the centre of gravity. Mettl describes it as making "the candidate's system into a safe lockdown mode" and preventing background applications. The candidate guide is blunter: the secure browser "shuts down all active applications, such as other browsers and cheating tools," and prevents candidates from "opening unauthorized websites or accessing blocked software/third-party applications." It also "restricts access to different activities, such as switching to other websites and screens during the exam."

You download and install MSB before the test. Mettl recommends taking a mock test through it first.

Screen sharing and external displays

Mettl handles this explicitly, and the rules are strict. If your screen is being shared before MSB starts, it "will only let the candidate begin the test once they remove the screen-sharing cable." After the test starts, "the test will terminate if the candidate shares a screen after starting MSB."

Mettl even documents the two cases it recognizes: an external screen connected by cable, and casting over Wi-Fi via something like Chromecast or a Firestick. Its guidance to candidates is to disconnect VGA, DVI or HDMI cables and use the PC-screen-only display setting.

Screen capture and camera snapshots every 60 seconds

The Screen Capture measure "captures the candidate's screen & Camera feed snapshots at every 60 seconds." Note that this is your screen, not just the test window.

Video recording and audio proctoring

Video Recording stores the complete webcam feed for later review. Audio Proctoring detects human speech and counts speakers, which is aimed at someone in the room feeding you answers.

Advanced visual proctoring, with named flags

This is the part candidates should read closely, because the flag names tell you exactly what the model is looking for:

FACE_NOT_VISIBLE
ANOTHER_PERSON
AWAY_FROM_WINDOW
CANDIDATE_LOOKING_AWAY
CANDIDATE_FACE_PARTIALLY_VISIBLE
CANDIDATE_NOT_PRESENT
MOBILE_PHONE_DETECTED

Mettl also captures your ID and facial images at the start for identity verification, and its proctoring guide describes live proctors who can pause or end a test and chat with a candidate in real time.

Browsing tolerance

Rather than a raw tab counter, Mettl uses a configurable Browsing Tolerance setting that monitors window navigation and issues warnings or auto-terminates the test depending on how the employer set it.

360-degree room check

A Mandatory 360 Check asks you to sweep the room with your webcam before starting. This is the measure aimed squarely at second monitors, second devices, notes, and other people.

Copy-paste, print-screen and watermarks

The "No Plagiarism" measure blocks copy-paste and print-screen controls. A background watermark is displayed to discourage photographing the screen, and questions and options are randomized.

IP restriction, OTP authentication and supervised resume

Employers can require you to sit the test from a defined IP range, verify you with a one-time password, and require proctor approval before you can resume after a disconnection. Attempting a proctored test walks through the candidate flow.

What Mercer Mettl cannot see

We want to be useful here rather than encouraging, so read this section as a description of limits, not as a plan.

What Mettl does not claim. Mettl's published anti-cheating list does not mention virtual machine detection, and its documentation does not describe enumerating and reporting every process on your machine as a candidate-visible feature. That is a narrow gap, and it is narrow on purpose: MSB's stated behavior is to shut down active applications rather than to inventory them.

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What is genuinely outside the machine. A physically separate device that never connects to the test computer is not something MSB runs on. That is true. It is also close to useless here, because Mettl has a dedicated MOBILE_PHONE_DETECTED flag, a mandatory room sweep before you begin, a camera snapshot every 60 seconds, and audio analysis listening for a second voice. The technical boundary and the practical boundary are not the same thing on this platform.

What no proctoring reaches. Your reasoning quality, and the network traffic of any tool you run. Neither of those helps you if the camera catches you looking at your lap once a minute for an hour.

The honest summary. On a fully configured Mettl exam, there is no configuration of any AI assistant we would describe as low risk, including ours. We have not benchmarked InterviewMan against MSB builds, and we are not going to invent a result. If a vendor tells you their tool is invisible to a lockdown browser plus 60-second screen capture plus a room sweep, ask them for their test methodology.

How Mercer Mettl scores or flags suspicious behavior

Mettl produces a proctoring report per candidate rather than a single suspicion number, and it stacks three layers:

Automated flags. The named visual flags above, audio events, browsing tolerance violations, blocked copy-paste and print-screen attempts, IP mismatches, and MSB violations.
Record and review. In the Basic+ style packages, a human reviews the recorded session at the points the AI flagged, rather than watching the whole thing.
Live proctoring. In the highest tier, a Mettl proctor watches in real time, can interact with you immediately when something looks wrong, and can pause or end the test. Mettl markets its AI flagging as achieving over 95% accuracy in detecting suspicious behavior, which is a vendor claim and should be read as one.

Auto-termination is the outcome candidates hit most often: sharing a screen after MSB starts, or exceeding browsing tolerance.

What recruiters see in the report

The employer receives your score plus a proctoring report containing the flag list with timestamps, the screen and camera snapshot gallery at 60-second intervals, the recorded video, audio event markers, the ID and face capture from registration, IP and access details, and any live proctor notes.

Because the flags are named and human-readable, a reviewer does not need to interpret a black-box score. "MOBILE_PHONE_DETECTED at 00:14:32" needs no explanation. That makes Mettl reports unusually easy to act on, and it is why candidates rarely get the benefit of the doubt here compared with a platform like TestGorilla, which deliberately softens raw flags into tiers.

Using an AI interview assistant on Mercer Mettl: what works, what is risky

What is technically true about our product. InterviewMan is a native desktop app whose overlay is excluded from screen capture and recording APIs, hidden from the dock, the taskbar and the app switcher. It never injects into a browser page. Its two-device Stealth Mode keeps the answer surface on a phone or second browser rather than on the interview machine. The full list is on our undetectability page.

Why that matters less here than anywhere else. Mettl's strongest measures are not browser code. MSB is an installed lockdown application. Screen capture takes your display, not the test window. The 360-degree room check and MOBILE_PHONE_DETECTED exist precisely to close the second-device gap. And CANDIDATE_LOOKING_AWAY is a flag whose entire job is to catch reading from somewhere other than the screen in front of you.

What breaks instantly. Screen sharing of any kind after MSB starts, which terminates the test. Browser extensions, which MSB blocks along with other third-party software. External monitors connected by cable, which MSB will not let you start with.

What we do not claim. InterviewMan does not hide network traffic, does not type or submit answers for you, does not execute code, and does not integrate with proctoring platform APIs. Zero confirmed detections across 570,000+ users is a track record, not a technical guarantee, and we have not measured it against MSB.

The policy question. Mettl assessments state their rules before you begin, and installing a lockdown browser is an unmistakable statement of intent. Using undisclosed assistance breaks that agreement, and in the academic and certification contexts Mettl also serves, the consequences reach further than a rejected application. Our balanced argument is in Should you use AI in a job interview in 2026?; the wider landscape is in which companies allow or ban AI in interviews.

Where an assistant is unambiguously fine. Preparation, and the human interview rounds that come after the test, where policies differ and no lockdown browser exists.

How to prepare for a Mercer Mettl assessment honestly

Install and test MSB early. Mettl recommends a mock test through the secure browser. Do it a day ahead, not ten minutes before.
Disconnect external monitors first. Cables and casting both block the start. Use the PC-screen-only display setting and unplug HDMI, VGA or DVI.
Clear your room before the 360 check. Notes on the wall, a second laptop, a tablet on the desk: all of it is on camera.
Check bandwidth and hardware. Mettl documents a 512 kbps minimum, a supported browser, pop-ups allowed for tests.mettl.com, and a working camera and microphone.
Practice aptitude and coding under time pressure. Mettl batteries often mix reasoning with technical questions. Our technical interview preparation guide and 10-step coding interview plan both fit.
Prepare the rounds after the test. A Mettl assessment is a filter. The interview that follows is where you actually get hired: see interview prep and AI mock interview practice.

How Mercer Mettl compares to CodeSignal, HackerRank, CoderPad and Codility

Platform	Lockdown app	Screen capture	Webcam	Audio analysis	Room check	Auto-terminate	What usually flags you
Mercer Mettl	Yes, Mettl Secure Browser	Screen and camera snapshots every 60 seconds	Yes, plus full video recording	Yes, speech and speaker count	Mandatory 360-degree sweep	Yes, on screen sharing and browsing tolerance	Named flags such as MOBILE_PHONE_DETECTED and CANDIDATE_LOOKING_AWAY
CodeSignal	No	Screen and webcam recording under AI Proctoring	Yes, plus ID check	Audio recorded	No	No	Suspicion Score, edit history
HackerRank	No	Browser-level proctoring	Optional	No	No	No	Tab exits, clipboard, extension checks
CoderPad	No	Interviewer watches the pad live	Only via the video call	Via the call	No	No	Paste events, typing playback
Codility	No	Browser events only	Optional	No	No	No	Tab switching, similarity
HackerEarth	Yes, Smart Browser (optional)	Records the test window	Frequent snapshots	No	No	Yes, at tab-switch threshold	Threshold breaches, plagiarism
Talview	Yes, lockdown browser	Live screen recording	Yes, plus secondary camera	Background voice detection	360-degree check	Configurable	Integrity score built from multiple flags

Mettl and Talview are the two platforms in this cluster built for high-stakes exams rather than developer screening, and it shows in every row.

Frequently asked questions

Does Mercer Mettl record my screen?

Yes, when screen capture is enabled it takes snapshots of your screen and camera feed every 60 seconds, and video recording stores the complete webcam feed. That is your display, not only the test window, which is a meaningful difference from browser-only platforms.

What does the Mettl Secure Browser actually do?

It puts your machine into a lockdown state. Mettl says it shuts down all active applications such as other browsers and cheating tools, prevents opening unauthorized websites or accessing blocked third-party software, and restricts switching to other windows or screens during the exam. You install it before the test.

Will Mettl terminate my test if I share my screen?

Yes. Mettl's candidate guide states that the test will terminate if the candidate shares a screen after starting the secure browser, and that if a screen is already being shared beforehand you cannot start until the cable is removed. Casting over Wi-Fi is treated the same way.

Does Mercer Mettl detect a mobile phone?

It has a dedicated flag for it, MOBILE_PHONE_DETECTED, as part of advanced visual proctoring. Combined with the mandatory 360-degree room check before the test and camera snapshots every 60 seconds, a phone is one of the worst second-device options on this platform.

Is there a human watching my Mettl test?

It depends on the package the employer bought. The basic tier is AI only. Middle tiers add record-and-review, where a human watches the parts the AI flagged. The top tier is live remote proctoring, where a Mettl employee monitors test takers in real time and can pause or end your test and message you directly.

How many tab switches does Mettl allow?

There is no single fixed number. Mettl uses a configurable Browsing Tolerance setting that monitors window navigation and either warns you or auto-terminates the test depending on how the employer configured it. Assume the tolerance is low.

Does Mettl detect virtual machines?

Virtual machine detection is not named in Mettl's published anti-cheating list, unlike HackerEarth, which advertises it explicitly. The secure browser's stated behavior is to shut down active applications and block third-party software rather than to inventory your system.

Can I use a second monitor during a Mettl test?

Not through a cable. Mettl's guidance is to disconnect VGA, DVI or HDMI cables and select the PC-screen-only display option before starting, and the secure browser will not let you begin while a screen is being shared.