Installing EEGLAB & plugins

Why do I need this step?

Every lesson after this one assumes EEGLAB runs on your computer, and that the Biosig plugin is installed so you can import EDF files in the import lesson.

How do I do it in EEGLAB?

1. Download EEGLAB

1. Open the official download page: Download EEGLAB.
2. Fill in the form: name and email, tick the box to accept the BSD license, then click Submit.
3. You get a ZIP file of the latest stable release.

2. Unzip it in a permanent place

Unzip the file in a folder you will not move later, such as Documents/MATLAB. You get a folder whose name starts with eeglab followed by the version number.

3. Save the path before the first run

Save the path before you type eeglab. The reason: when it starts, EEGLAB adds its subfolders to the path, and the save button saves the whole path as it is at that moment.

1. Open MATLAB, and do not start EEGLAB yet. If you already started it in this session, close MATLAB and open it again.
2. Type pathtool in the Command Window (or open Set Path from the MATLAB interface).
3. Click Add Folder and select the main EEGLAB folder only.
4. Click Save, then Close.

4. Start EEGLAB

Type eeglab in the Command Window and press Enter.

The EEGLAB main window opens with seven menus: File, Edit, Tools, Plot, Study, Datasets and Help. When it starts, EEGLAB adds its own subfolders to the path of the current session, without saving them.

From now on, typing eeglab in any new MATLAB session is enough.

5. Install the Biosig plugin

1. In the EEGLAB window, open File › then Manage EEGLAB extensions. This needs an internet connection.
2. The list of plugins appears. Plugins in bold are installed on your computer, and red ones need an update.
3. Click the search button at the top of the window and type Biosig.
4. Select Biosig in the list, then click Install/Update.
5. EEGLAB downloads the plugin and rebuilds its window. Biosig reads EDF, BDF and many other formats.

The extension manager shows each plugin’s star rating and download count, and sorts the list by downloads. When two plugins do the same job, these two numbers are a quick first guide. For what each common plugin does and when you need it, see the Plugins guide.

How do I write it as code?

The same steps from the command line. Run it once after unzipping EEGLAB, in a new MATLAB session where you have not started EEGLAB yet.

% Go to the EEGLAB folder (change the path to yours)
cd('C:\Users\me\Documents\MATLAB\eeglab2026.1');

% Save the root EEGLAB folder in the path BEFORE starting EEGLAB,
% so its subfolders are not saved too
addpath(pwd);
savepath;

% Start EEGLAB; it adds its own subfolders for this session only
eeglab;

% Install Biosig only if it is not installed yet (needs internet)
if ~exist('sopen', 'file')
    plugin_askinstall('Biosig', 'sopen', true);
end

• addpath(pwd) then savepath save the main folder only, because they come before eeglab. If they came after it, savepath would save all the subfolders EEGLAB added, which is what the documentation warns against.
• sopen is a Biosig function. If it exists, the plugin is installed and there is no need to install it again.
• The third argument, true, installs the plugin without a confirmation dialog, so it works inside a script.

Which value should I choose?

The only decision here: where do you get MATLAB? The options go from best to weakest for these lessons.

MATLAB release: the EEGLAB team recommends a recent, though not necessarily the newest, MATLAB release. If you have MATLAB 2016a or older, the download page points you to EEGLAB 2020.0, which this site does not cover.

Updating: in the MATLAB version you find Help › then Check for EEGLAB update, and EEGLAB prints at startup whether you have the latest release. But these lessons are written for EEGLAB 2026.1, so do not update in the middle of the course. Menu names and numbers may change in a newer release.

How do I check it worked?

1. The window: the EEGLAB main window opened with its seven menus.
2. The path: close MATLAB, open it again, and type which eeglab. It should print the path of eeglab.m inside your folder. And when you run eeglab, no red warning about subfolders should appear.
3. The version: type eeg_getversion. It should print a version number starting with 2026.1.
4. The plugin: type exist('sopen', 'file'). A result of 2 means Biosig is installed. Its name also appears in bold in the extension manager.
5. Startup lines: each time EEGLAB starts, it prints one line per plugin it loads in the Command Window, starting with EEGLAB: adding followed by the plugin name and version. Look for Biosig.

What mistakes do people make?

• Downloading the ZIP from GitHub instead of the download page. You miss essential plugins such as ICLabel, clean_rawdata and firfilt. Red warnings appear at startup for the first two, and EEGLAB asks to download firfilt the first time you filter.
• Saving the folder with all its subfolders. This happens with the Add with Subfolders button, or by saving the path after running eeglab in the same session. The documentation advises saving the main folder only, and EEGLAB prints a red warning at startup if it finds its subfolders saved.
• Keeping an old EEGLAB release in the path. If you install a new release, remove the old one in Set Path with the Remove button. Otherwise MATLAB may call outdated functions.
• Looking for the extension manager in the compiled version. The menu does not exist there at all. If you need a plugin it does not include, you need the MATLAB version.
• savepath or the Save button fails. This usually happens when your account cannot write to the MATLAB folder. Run MATLAB as administrator once. Or create a file named startup.m in the folder printed by the userpath command, and write one line in it: addpath followed by the EEGLAB folder path in parentheses. MATLAB runs this file automatically at the start of every session, and it needs no special permissions.

Going further

• EEGLAB Tutorial: https://eeglab.org/tutorials/01_Install/Install.html (1. Installing EEGLAB)
• EEGLAB Extensions: https://eeglab.org/others/EEGLAB_Extensions.html (To install or update a plugin)
• Download EEGLAB: https://eeglab.org/others/How_to_download_EEGLAB.html (Download the EEGLAB ZIP file archive)
• The compiled version of EEGLAB: https://eeglab.org/others/Compiled_EEGLAB.html (Installation)
• Running EEGLAB on Octave: https://eeglab.org/others/Running_EEGLAB_on_Octave.html (Running EEGLAB on Octave)
• MATLAB Online Versions (MathWorks): https://www.mathworks.com/products/matlab-online/matlab-online-versions.html (MATLAB Online (basic))