DECL file format description

Many people share .decl files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .decl file can be edited, converted or printed with. On this page, we try to provide assistance for handling .decl files.

1 filename extension(s) found in our database.

.decl - Doom 3 Declaration Data

The DECL game data files are related to Doom 3. The DECL file is a Doom 3 Declaration Data. Doom 3 is a science fiction survival horror first-person shooter video game developed by id Software.

Doom 3
Game Data files
- / -
Doom 3 Declaration Data related extensions:
NASCAR Racing 2002 Arcade Car Setup
B.O.U.T. Evolution Low-res Texture Data
id Tech 6 Index Data
Monster Hunter: World SkillGem Parameters Data
Half-Life Map Collision Hull Data
Xpand Rally Xtreme Replay Data

Naturally, other applications may also use the .decl file extension. Even harmful programs can create .decl files. Be especially cautious with .decl files coming from an unknown source!

Can't open a .decl file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following message:

Windows can't open this file:


To open this file, Windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually select one from a list of programs that are installed on your computer.

To avoid this error, you need to set the file association correctly.

The .decl file extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

dcl, dec, deck, del, ecl

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

BricsCAD Dialog Control Language Data
Creator Simulator Temporary Data
PCTracker Undelete Tracking Data
VersaPro Declaration File
DumpSec Report
Mass Mailing News E-Campaign List

Operating systems currently supports the following operating systems:

Windows XP/Vista, Windows 7/8/10, Windows 11, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, macOS, Mac OS X, iOS, Android

If you find the information on this page useful, please feel free to link to this page.

If you have useful information about the .decl file format, then write to us! >> DECL file