DAD File

What are DAD files and how to open them

Are you having problems opening a DAD 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 DAD files.

What is a DAD file?

A .DAD file is a Chromeleon Channel RAW Data file.

Chromeleon Channel RAW Data files store the unprocessed detector signals recorded by the Chromeleon Chromatography Data System when using a diode-array UV/Vis detector. These raw data are digitized over time at one or more wavelengths during a chromatography run, capturing the absorbance or signal trace for each detector channel so that peaks, baselines and other analytical features can be inspected or reprocessed later.

These files are generated by Thermo Fisher Scientific's Chromeleon software (originally Dionex Chromeleon CDS). During a run, each detector channel creates a separate binary file to preserve raw signals. The data are then accessed and interpreted only within Chromeleon. Export to open formats (such as netCDF/AIA-CDF, CSV or ASCII text) is possible from within Chromeleon so data may be shared or analyzed outside the system. Raw data file size depends on run duration, sampling (data collection) frequency, and the number of wavelengths collected.

The format is proprietary, little-endian binary, with no public documentation of all internal layout or versioning. These files are not designed as standalone archives: they coexist with other Chromeleon-files in a sequence or data source folder (for example, sequence metadata files, quantitation files, etc.). Typical Chromeleon workflows hide the raw channel files from default user views, managing them through the data browser rather than file system navigation.

Identification of these raw-channel files can be aided by internal signatures: they often begin with the ASCII string "YREC" (followed by bytes 0x0000010003000001) at the very start, and include the text "TEMP" somewhere within the file, among other internal markers.

How to open DAD files

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

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

Last updated: September 21, 2026

Various apps that use files with this extension

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