CotEditor

CotEditor is a free, native macOS plain-text editor for source code, configuration files, markup and everyday text. It provides syntax highlighting, document outlines, line numbers, character information, split editing, regular-expression find and replace, and tools for text encodings and line endings. It edits the text itself rather than producing a rich-text layout like a word processor.

Editing text and folders

Open a text file or folder, choose a syntax and inspect the text in one or more views. Folder search in7.1 can search across files in an open folder. Modes let you select indentation style and width for different workflows. The editor supports conversion of line endings and encodings, with tools to inspect characters and identify text that cannot be represented in an encoding. Verify the result when converting files used by another program; an encoding or line-ending change can affect compatibility.

Find and replace supports regular expressions and reusable replacement definitions. Use the appropriate scope and review matches before Replace All, especially across important files. CotEditor is a text editor, not a full IDE, compiler or debugger; editing a script does not install its language runtime or dependencies.

Installation and compatibility

CotEditor7.1.1 requires macOS26 Tahoe or later and runs natively on Intel x86-64 and Apple Silicon ARM64. Its direct-download DMG is26,594,816 bytes before installed storage. Copy the app from the DMG to Applications and open it. The7.0.9 historical release requires macOS15+, but that does not change the current7.1 requirement.

The direct download is free and needs no CotEditor account, subscription or activation. The Mac App Store is another distribution route and uses the usual Apple Account requirements. The direct-download edition uses Sparkle for updates; the App Store edition follows App Store updating. Document access is sandboxed and based on user-selected files and folders, so provide access through the app's supported file-opening workflow rather than assuming it can freely modify every protected path.

Scripts and automation

CotEditor supports scripts from its Script menu, including AppleScript and executable UNIX scripts. A UNIX script can receive selected text or document content through standard input and return output to the editor. Scripts require an available interpreter and must use an appropriate file extension and executable permissions.

Python scripts need a compatible Python interpreter installed separately. The official guide supports a shebang such as /usr/bin/env python3, but warns that CotEditor's PATH can differ from the Terminal shell's PATH. Specify an absolute interpreter path when a particular environment is required. The editor does not promise a bundled Python runtime or universal compatibility with every package environment. Run only trusted automation: scripts can change document content and perform other operations within their available permissions.

Saving and recovery

CotEditor provides macOS-style automatic saving and recovery mechanisms for editing work, but these are not independent backups. Saving, replacing text or running a script can change the actual document. Keep version control or separate backups for important files and review converted or rewritten documents before using them elsewhere.

License and cost

CotEditor is free and open source. Its current source-code license is Apache License2.0, while image resources have a separate Creative Commons Attribution-NonCommercial-NoDerivatives4.0 license. The source license is not a blanket license to reuse every project graphic. There is no required paid plan for the editor.

Official sources: CotEditor, Source and requirements, 7.1.1 release, UNIX scripting guide, License.