CEL File

What are CEL files and how to open them

Are you having problems opening a CEL 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 CEL files.

What is a CEL file?

CEL files have multiple uses, and Affymetrix Probe Results is one of them. Read more about the other uses further down the page.

Affymetrix Probe Results

These CEL files contain information on the probe set's intensity values, and a probe set represents a gene. Information about probes gets extracted from the image data by Affymetrix, an image analysis software.

How to open CEL files

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

While we have not verified the apps ourselves yet, our users have suggested ten different CEL openers which you will find listed below.

Last updated: August 31, 2026

All known file formats using extension .CEL

While Affymetrix Probe Results is a popular type of CEL-file, we know of 8 different uses of the .CEL file extension. Different software may use files with the same extension for different types of data.

Audition Loop

Audition Loop format stores short audio loops with embedded metadata so that software can match their beat, tempo, and key to a musical project. These files are created by Adobe Audition (formerly Cool Edit) and were originally distributed in Adobe's Loopology loop library. Their primary use is for musical and sound design work, letting Audition users drag loops into multitrack projects where the loop seamlessly repeats and matches project settings.

An Audition Loop file contains compressed audio data (similar to MP3, sometimes using mp3PRO-style compression) along with a custom header that includes loop-specific metadata. This header stores the number of beats, the loop's original tempo, its musical key, and the stretch method so that Audition can adjust playback to fit a session. The format also remedies a problem common to MP3 encoding where small amounts of silence are added at the start or end of the file: Audition records how much silence would be added, and when loading the loop it automatically removes it so the loop plays back seamlessly.

Files in this format begin with specific internal identifiers and markers that uniquely identify them. They start with the two bytes 0xFFFA at offset zero, and contain strings such as "ADOBE AUDITION LOOPOLOGY", "WAVEDISP", "INFOWBPSE", "INFOIART", "INFOISFT", "SYLPTAG", and "ABLMA" within the data.

Bentley MicroStation CAD Cell library

These CEL files contain complex elements created in Bentley MicroStation, a design and construction software. CEL files are used to eliminate the repetitiveness of redrawing the same elements in a floor or building plan. These CEL files can be found under the Cell library for everyone, who is part of the project, to use.

CEL opener for Windows

We have identified 2 CEL openers that are compatible with this specific type of CEL file.

Celestia script

These CEL files contain the simulated versions of the universe used in Celestia, a 3D astronomy software. Celestia grants you the opportunity to traverse a simulated universe. You can view the stars, planets, and moons at different speeds and sizes.

Programs that open these CEL files

We have identified one CEL opener that is compatible with this specific type of CEL file.

Chasm CEL bitmap

These CEL files contain information on the color index used to indicate transparent areas on images in Chasm: The Rift, a first-person shooter game.

Cyber Paint Cell Animation

We know that one CEL format is Cyber Paint Cell Animation. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

KiSS CEL Bitmap

KiSS CEL Bitmap files store graphics used in the Kisekae Set System (KiSS), a digital paper-doll/dress-up art program. These files represent individual cel graphics - that is, movable image elements such as hair, clothes, eyes - that can be layered, positioned, and displayed with transparency to build a complete doll set. They are written by tools following the KiSS/General Specification (KiSS/GS), to be used by KiSS viewers or editors.

Each cel holds pixel-based image data, either palette-based (4-bit or 8-bit index into a color palette) or full-color with transparency (32-bit RGBA). They include header fields that specify width, height, pixel format, and position offsets used when layering multiple cels. Such graphics are not compressed and are intended for overlaying and combining with other cels according to a configuration within a KiSS "set."

Modern files follow a 32-byte header layout starting with the signature KiSS, then a byte marking whether the cel is palette-based or full color with alpha, a byte for bits per pixel (4, 8 or 32), two reserved bytes, and fields for width, height, X-offset and Y-offset from the top-left alignment point. The remaining header space is reserved. If the file does not begin with the KiSS identifier, it uses an older format with just width and height (each 2 bytes) followed immediately by 4-bit palette‐indexed pixel rows.

TurboSilver Cell/animation Data

TurboSilver Cell/animation Data files store 3D object, camera, lighting and animation information used by TurboSilver 3.0, a ray-tracing and animation system by Impulse. They represent "cells" - key frames or scenes - each containing complete scene descriptions: object hierarchies, global properties such as ambient lighting and sky, camera position and motion, textures, materials, and animation paths ("Stories"). The format lets users build individual cells and then generate animations by interpolating motion and other changes over multiple cells.

TurboSilver writes these files when saving cells or animation key-frames from its Animation Editor and Object Editor. Other components of its workflow may read them later: the Make Scene command renders images frame by frame from the cell data; the Animation Editor also loads cells for editing or combining. These files are part of TurboSilver's scene storage, distinguishing scene description (CEL files) from rendered stills and final movie frames.

Internally, it is an IFF-style file based on the TDDD (3D Data Description) FORM. It begins with the signature FORM at offset 0, includes a "TDDDINFO" chunk around offset 8, and uses IFF sub-chunks like INFO for observer or camera metadata, OBJ for object trees, plus sub-chunks like AMBI (ambient light), FADE (fade effect), GLB0 (global properties), SKYC (sky horizon/zenith colors), OBSV (observer data), and OTRK (object tracking). Numerical values such as fractional coordinates ("FRACT") are stored as 32-bit integers interpreted with fixed-point scaling.

Various apps that use files with this extension

These apps are known to open certain types of CEL files. Remember, different programs may use CEL 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 CEL file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.