What is Safe Exam Browser?
Safe Exam Browser is, in the words of its own project site, a web browser environment to carry out e-assessments safely. It is developed at ETH Zurich, which has published it since 2010 as freeware with source code under the Mozilla Public License. The software turns any computer temporarily into a secure workstation: it controls access to resources like system functions, other websites, and applications, and it prevents unauthorized resources being used during an exam.
The project publishes three versions. SEB for Windows runs on Windows 8.1, Windows 10, and Windows 11 and is built on the Chromium browser engine. SEB for macOS and SEB for iOS use the WebKit engine that Safari is based on, with current versions supporting iOS 12 and newer. All three are configured per exam through encrypted settings files, so what your exam blocks can differ from what another institution's exam blocks.
SEB is not a proctoring service. The official overview states that SEB does not connect to any central server or cloud service, and by itself it produces no recording of you or your screen. It is the lockdown half of an exam setup - the half that controls the machine. The watching half, when a program wants one, comes from a separate proctoring layer, which is why candidates often meet SEB together with a live or recorded proctoring tool.
How SEB works: kiosk app, browser, exam system
The official architecture has two components on your computer. A kiosk application locks down the examination computer, and a browser part communicates over the internet - or a local network - with the quiz module of a learning management system or an e-assessment platform. The browser displays the exam page using a preset start address and shows no address bar, no search field, and, depending on the configuration, no navigation controls at all.
SEB connects to web-based exam systems rather than replacing them. The project names Moodle, ILIAS, OpenOlat, Open edX, and Canvas as systems with an explicitly SEB-compatible exam mode, and states that SEB generally works with basically any web-based exam system. The integration is two-way: an exam can be configured to run only with SEB and to refuse every ordinary browser.
Every exam gets its own settings. Starting with version 2.0, SEB offers an individual configuration per exam, protected by strong encryption against manipulation. The configuration travels as an encrypted settings file or as a special hyperlink that starts SEB from another browser and reconfigures it for that specific exam. Because the rules live in the file, your university's SEB exam can look and behave differently from another institution's.
An authentication feature lets the exam system check what is connecting to it. The project publishes that the exam system can verify that a particular, unaltered SEB version and the correct exam settings are being used for an examination; the Windows manual documents this Browser Exam Key check for Moodle and recommends it for bring-your-own-device scenarios. The official FAQ describes a real case in which altered files in SEB's program directory changed the Browser Exam Key, which would usually prevent access to an exam that enforces the check - published evidence that a manipulated installation fails verification.
Exam organizers can optionally allow specific third-party applications to run during the exam. The official overview names Eclipse, Matlab, Excel, and R as examples; an allowed application is started by the SEB kiosk application and can be switched to from the SEB taskbar. By default, nothing else runs.
What SEB locks down, by platform
The kiosk layer's job is to make the computer single-purpose for the duration of the exam. When SEB starts on Windows, all currently running applications, the Windows taskbar, and the desktop are hidden, and the browser window fills the screen. When SEB quits normally, the applications that were running before are unhidden again, unless the exam settings forced them to quit.
The categories below are the vendor's own published lists of what is disabled in default settings on each platform. Your exam organizers choose the actual configuration, so a specific exam can be stricter or looser than the defaults.
Two patterns repeat across all three platforms. First, the exam browser itself is stripped down: no address bar, no search field, no right-click context menu in the browser window, and navigation controls that can be disabled entirely. Second, capture and switching are the consistent targets: whatever would let content leave the exam window, or let another application share the screen, is disabled by default.
Published lockdown categories in default settings, by platform
| Platform | Lockdown categories published by the SEB project |
|---|
| Windows | Taskbar and Start Menu hidden; switching to other applications with Alt+Tab or Windows+Tab blocked unless permitted; menu options on the Ctrl+Alt+Delete security screen removed while SEB runs; Print Screen and shortcuts such as Alt+F4 blocked; display and system idle sleep disabled; separate kiosk desktop modes available |
| macOS | Quitting disabled or protected by a quit password; Dock and Menu bar hidden; application switcher with Cmd+Tab blocked; Force Quit window blocked; hiding or minimizing the window blocked; printing, right-click, and macOS screen capture disabled |
| iOS | Apple's built-in Assessment Mode blocks switching to other apps, other websites, and communication with other students; notifications, FaceTime and voice calls blocked; screenshots blocked; screen capture over AirPlay or cable blocked; quit password required for the secure mode |
Scroll horizontally to view all columns.
Process, website, and connection controls
Beyond the visible lockdown, administrators configure two process lists. A permitted-processes list defines what may run alongside SEB, and a prohibited-processes list defines what may not. The published behavior is that process monitoring hides or terminates not-allowed processes while SEB is running, and that SEB always asks you to quit prohibited applications manually when it starts up.
One layer of that list is not optional. The Windows manual publishes that since version 2.1.7, some default processes are blocked automatically because they could be used for cheating; they are added automatically to every SEB configuration and cannot be removed from the prohibited list. The project does not publish that internal list as candidate-facing documentation, and this page does not enumerate it - the general category is what matters: software the exam does not allow does not stay running.
On the network side, a URL filter allows accessing only specific websites, pages, or resources, which means the open internet is unreachable from the exam browser unless your exam explicitly allows a site. Certificate pinning is published as protection against man-in-the-middle attacks on the connection to the exam server. Spell checking and dictionary lookup are disabled by default and can optionally be allowed by the exam configuration.
The browser part itself is purpose-built. On Windows it is based on the Chromium Embedded Framework; on macOS and iOS it uses the system's WebKit engine, the same family Safari uses. In both cases it loads the exam's start address and nothing else, with no way to type a different address.
Virtual machines, lock screens, and quitting
SEB publishes a virtual machine check. The Windows manual states that SEB detects when it was started in a virtual instead of a native environment and refuses to run if the exam settings do not explicitly allow it, and describes the purpose plainly: helping avoid manipulation of the exam environment when SEB is used on unmanaged computers like students' own laptops. The project's general feature list extends the same idea to jailbroken devices, which SEB can also refuse to start on.
Quitting is deliberately ordinary under default settings. You press the Quit button in the SEB taskbar or the Ctrl+Q shortcut, the kiosk layer closes, and your previous applications reappear. Exam organizers can change both ends of that: quitting can be switched off entirely, or it can be protected by a quit password.
The official FAQ is blunt about that password: there is no default SEB quit password. It is always set up by the people who set up the exam, the SEB project does not know it and cannot find it out. If the exam is correctly set up, submitting the exam makes the exam system display a button or link that unlocks the device and quits SEB without any password at all.
The same FAQ explains the red lock screen. SEB sometimes displays one when something happens during the exam which would make the exam insecure; the published candidate instruction is to contact your exam support - the organizers, teacher, or proctors - because they hold the password. The practical advice from the same source is to save all documents and ideally quit applications with open documents before starting SEB.
Why institutions pair SEB with proctoring
The recording boundary is published and absolute: SEB does not connect to any central server or cloud service. Out of the box it produces no recording, no webcam feed, and no behavior flags. It controls the machine, not the person - a lockdown browser cannot tell who is sitting in front of the screen, whether a second person is in the room, or what is on the desk.
That gap is the entire reason for pairing. Programs that need assurance about identity and behavior add a proctoring layer on top of SEB: a live proctor watching by webcam, a record-and-review service, or an institution-run video setup. The lockdown handles the device; the proctoring handles the person. Our comparison of online proctoring software maps where those proctoring layers differ.
SEB also offers its own optional management layer. SEB Server is an independent open-source component that an institution installs on a self-operated server and connects SEB clients to through individual configuration files. The published consent rule matters to candidates: if a client is configured to connect to an SEB Server instance, this is indicated when the exam session starts, and video or audio proctoring and support must be explicitly agreed to by each exam candidate in a dialog box.
The pairing is enforceable at the door, not just on paper. Because an exam can be configured to run only with SEB, and because the Browser Exam Key lets the exam system verify a particular unaltered SEB version with the correct settings, a candidate cannot arrive with a different browser or a modified installation and simply proceed.
Platforms, system impact, and removal
Platform coverage is exactly as published. SEB for Windows supports Windows 8.1, Windows 10, and Windows 11. SEB for macOS supports macOS versions from 10.11 through the current releases. SEB for iOS supports iOS 12 and newer on current versions. The project offers downloads and manuals for those three platforms, which is the full published list.
On Windows, SEB temporarily changes the system while it runs. The official FAQ states that it changes Windows Registry settings for the options on the security screen invoked by Ctrl+Alt+Delete, remembers the values that were active before, and resets them to the original values when SEB exits regularly. The same source documents the fallback paths - a restart, a proper re-quit, uninstalling, or a small registry-resetter tool - for the unlikely case the restoration fails.
The damage question gets a direct official answer: the FAQ states that SEB cannot damage your computer, software, or documents. The software is freeware provided without warranty, it uninstalls like a normal application, and the project is explicit that support responsibility sits with your exam organizers, because they chose and configured the exam setup.
Connectivity is the one thing SEB cannot lock down. The browser part communicates over the internet with your exam server, so the exam depends on that connection holding. The project does not publish reconnection rules, so what an interruption means for your attempt - saved answers, re-entry, rescheduling - is set by your exam system and your organizers' exam policy, and it is worth asking them before test day.
If the Sitting Itself Is the Problem
Understanding what SEB restricts is one thing; sitting a locked-down exam is another. Exam Assist exists for exactly that gap - we handle online exam sittings end to end, and the service fee is due only after your agreed result posts. Send your exam, your window, and your deadline, and you will get an honest feasibility answer first.
If you want the wider picture first, our guides to how online proctoring works and the comparison of online proctoring software explain where the SEB model sits among its competitors, our Respondus LockDown Browser overview covers the other big lockdown browser, our online proctoring software explainer breaks down the monitoring layers programs add on top, and our what-to-expect walkthrough covers exam-day check-in step by step.