.SID File Extension

A .SID file is a MrSID Image, created by Valve.

Open with Valve Steam+. Available for Windows and Mac.

What is a .SID file?

File Extension: .SID File Type: MrSID Image Description: A .SID file is a backup file used by Steam, which is a program that lets you download and manage video games made by Valve on your computer. This file contains compressed data from a game, which is created using Steam's backup feature, specifically with a tool called steambackup.exe. The purpose of a .SID file is to save a copy of game data so that it can be stored on DVDs or other external storage devices.

Programs that Open This File: Valve Steam

More Information:

.SID files are associated with two other file types: .SIS and .SIM. These files contain important information (metadata) that is needed to restore the game data from the backup. The naming format for .SID files usually follows this pattern: {game}_disk{X}_{Y}.sid. Here, "game" refers to the name of the game being backed up, "X" represents the disk number, and "Y" indicates the file number on that particular disk.

It's important to note that Steam backups created using .SID files do not include saved game progress, custom multiplayer maps, or game configuration settings. These elements must be backed up separately and restored manually if needed.


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