When you look at the “Activity” view in the ActivityWatch UI you will see that there are some visualizations based on “categories”.

Categories are used to group together multiple events, which create more easily understandable labels for the data such as “Work”, “Gaming” or “Social Media”.

Each category has a title, a parent category (optional), child categories (optional), and a categorization rule which is used to match events on window titles and application names.

A category can have child categories (“Work” might have “Mail”, “Gaming” might have “Minecraft”, etc). Child categories have independent categorization rules, but the time attributed to the children of a parent category is often added to the parent category in visualizations.

Adding and editing categories

If you go to the “Settings” page in the ActivityWatch UI, there is a section called “Categorization” which lists all the current categories and its respective sub-categories. You can add new categories and edit existing categories in this view. When editing categories you have the option to name them, change their parent category, and set a rule for them.


A rule decides what text will match in an event. If there are multiple categories matching the same event then the deepest sub-category will be chosen.

Currently there are only two rule options for categories: “Regex” or “No rule”.

Regular expressions (RegEx)

“RegEx” is short for “Regular Expression” and is a way to express a text pattern. The regular expression is matched on the ‘app’ and ‘title’ value of events (not yet URLs).


We do not support matching URLs from the web watcher yet, but it is a planned feature. You can work around this by using a browser extensions that adds the URL to the window title (Chrome, Firefox).

There are lots of great guides online where you can learn to write regular expressions. There are also sites like where you can easily try out patterns.

Note that some characters have special meaning in regular expressions, notably: . (period, acts as wildcard for any character), $ (matches end of string), ^ (matches start of string), +, *, ?, and brackets of all kinds.

With some care, these can be escaped (often by wrapping them in a ‘character class’, like this: [.]).


  • Gmail|Thunderbird will match events containing either Gmail or Thunderbird

  • ^Settings$ will match events with app or title being exactly Settings

  • An empty string will match everything, so be careful!

    • If you want a category without a rule, use the ‘No rule’ rule type instead.

The regex engine used by ActivityWatch is the one from the Python programming language (of if you use aw-server-rust, the engine provided by the regex crate).

No rule

“No rule” simply means that the category will not match anything (but its child categories still might). You can use this to create category groups which won’t get matched themselves, but only be used as ‘folders’ for child categories.

In the future we might take a look at adding some other rule type to more easily express text patterns.