ASD File Extension

By Shea Laverty

The ASD file extension is primarily used by Microsoft Word, a word-processing program included in Microsoft's Office software. ASD files are used as part of the recovery system for Word, should the program crash or freeze. There are a few other programs that utilize the extension, but Word is the most commonly associated program to employ it.

Word AutoSave File

ASD files are automatically created by Microsoft Word as part of the program's recovery system. These temporary autosaves are periodically created on open documents so that if an error occurs and the program or computer freezes, glitches or crashes, you have the option to restore what you were working on during the next startup. These saves are stored separately from the actual file, in the "temp" folder unless otherwise directed via the Settings menu.

Compatible Versions

ASD files are compatible with all versions of Microsoft Word. It was also the default autosave file for older Microsoft Word versions, including 95a, 95, 97, 2000, 2002, 2003 and 2007.


As of the time of publication, the latest edition of Microsoft Word, Microsoft Word 2010, uses a different file extension -- WBK -- for its default autosave files. However, ASD files are still compatible with Microsoft Word 2010 and can still be opened from this program.

Other Programs

Other programs make use of the ASD file extension as well. Gold Disk Inc.'s Astound presentation software uses it for its presentation files, and Lotus uses the extension for the screen drivers of its 1-2-3 program. Alphacam computer-aided drafting software makes use of the ASD extension for stone drawing files, and Ableton Live uses the format for audio analysis files.