CLN File

What are CLN files and how to open them

Are you having problems opening a CLN file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your CLN files.

What is a CLN file?

A .CLN file is an OpenToonz Cleanup Settings file.

OpenToonz Cleanup Settings files store configuration data that control how scanned drawings are cleaned up and prepared for animation. These files are created by the OpenToonz program when the user configures settings in the Cleanup Settings dialog - parameters for cleaning up lines, geometry, camera cropping, resolution, and color processing. They hold all the values that determine how input raster scans will be processed to produce clean, paintable raster levels.

These files are intended to be saved by the user after setting options for the cleanup process. They can be loaded later into new scenes or applied to specific animation levels by placing them in the same folder and giving them the same name as the level. When loading or applying cleanup, the program reads these settings and uses them to process the scanned images - removing noise, recognizing outlines, adjusting line sharpness and contrast, fixing antialiasing, mapping colors (in lineart or color mode), cropping, rotating, or flipping the image.

Internally, the settings file is stored in a human-readable XML-like format. The file begins with a version tag (for example ".version" near the start) and contains field-value pairs and keywords identifying settings such as LINEPROCESSING AUTOADJUST, CLOSESTFIELD VALUE, DESPECKLING VALUE, CLEANUPPALETTE, CAMERAXPREVALENCE, NOANTIALIAS, SHARPNESS, STYLEPAGES, COLOR_0, INDICES, STYLES, MODE, PATH, among others.

How to open CLN files

Important: Different programs may use files with the CLN file extension for different purposes, so unless you are sure which format your CLN file is, you may need to try a few different programs.

While we have not verified the app ourselves yet, our users have suggested a single CLN opener which you will find listed below.

Last updated: August 31, 2026

Various apps that use files with this extension

These apps are known to open certain types of CLN files. Remember, different programs may use CLN files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about CLN file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.