.EFI File Extension

Extensible Firmware Interface File

An EFI (Extensible Firmware Interface) file is a system file used by Intel-based computers and devices like Apple TVs. It contains instructions that help the system boot, run pre-boot programs, and apply firmware updates. These files act as a bridge between the system's firmware and the operating system, allowing smooth communication during startup and improving the boot process. EFI was originally created by Intel in the late 1990s and later evolved into UEFI (Unified Extensible Firmware Interface), which is now managed by the UEFI Forum.

EFI files are essential during the boot process. They are stored in a special hidden partition called the EFI System Partition (ESP). When a computer starts, it looks for these files to load the operating system or a pre-boot environment.

For example, Windows systems typically search for specific EFI files such as:

• \EFI\boot\bootx64.efi (for 64-bit systems)
• \EFI\boot\bootia32.efi (for 32-bit systems)

If a computer does not have an operating system installed, it will search for EFI files on connected drives or media to begin the installation process. These files are also used for updating firmware, allowing manufacturers to deliver essential system updates.

How to Open .EFI as Extensible Firmware Interface File

EFI files are not meant to be opened by regular users. They are executed automatically by the system during boot. However, advanced users or developers can view and modify EFI files using specialized tools like the EFI Developer Kit (EDK). These tools are primarily used for creating custom firmware, drivers, and applications that run during the pre-boot stage.

For most users, there is no need to open or edit EFI files, as they are a critical part of the system's boot and firmware management process.

Applications That Open EFI Files

Windows Apps for EFI Files:

• EDK II Free

macOS Apps for EFI Files:

• EDK II Free

Linux Apps for EFI Files:

• EDK II Free