What Features Does CotEditor Offer for macOS Users?

CotEditor is a free, open-source plain-text editor built specifically for macOS. It is lightweight and launches quickly, and its feature set centers on everyday writing and coding tasks: syntax highlighting for 60+ languages, ICU regular-expression find and replace, GUI-based settings, automatic backup, and a set of editing utilities. It suits macOS users who want a fast native editor for plain text, code, and Markdown without a heavy IDE.

Core editing features

Syntax highlighting

CotEditor colorizes more than 60 pre-installed major languages, including HTML, PHP, Python, Ruby, and Markdown. You can also create your own syntax settings if a language you use is not covered.

Find and replace

The find-and-replace function uses the ICU regular expression engine, which supports powerful pattern matching for search and substitution.

Outline menu

The outline menu extracts specified lines based on the predefined syntax, and you can jump directly to the corresponding line in the document.

Split editor

You can split a window into multiple panes to view different parts of the same document at the same time.

Character inspector

Select a character and the character inspector displays its Unicode character data in a popover.

Incompatible character check

CotEditor can check and list the characters in your document that cannot be converted into a desired encoding, which helps before saving or exporting to a specific encoding.

Configuration and workflow

Settings via a standard window

There are no complex configuration files requiring technical knowledge. All settings, including syntax definitions and themes, are accessible from a standard settings window.

Auto backup

CotEditor automatically backs up your documents while you edit, so unsaved data is not lost.

Scriptable macros

You can write your own macros in a range of languages: Python, Ruby, Perl, PHP, UNIX shell, AppleScript, or JavaScript.

macOS and CJK-specific behavior

• Made for macOS: CotEditor is designed specifically for macOS and behaves like a native macOS application.
• Rapid launch: It launches quickly so you can start writing immediately.
• CJK language friendly: It estimates various file encodings accurately, can toggle to vertical text mode, and keeps line height correct in that mode.
• Open source: CotEditor is developed as an open-source project that accepts contributions, and bug reports or feature requests go through its issue tracker.

Quick reference

The site states CotEditor is free, lightweight, and open source. If your work is mostly plain text, code, or Markdown on macOS and you want native behavior, fast startup, and scriptable macros without a full IDE, these features cover that use case.