What is the Difference Between UEFI and Legacy?

The UEFI Unified Extensible Firmware Interface” is the next-generation interface between the operating system and the platform. However, the Legacy Boot denotes the boot process utilized by the firmware of the BIOS (an acronym for Basic Input-Output System).

The aim of this guide is to illustrate the difference between UEFI and Legacy based on their features and functionalities.

The outline of this post is written below:

Let’s started with the basic information about UEFI.

What is UEFI?

The “UEFI” supports the “Graphical Mode”. The UEFI supports the 32 or 64-bit operating system.

The UEFI can get all the system memory. It uses a new partition team called “Grid Partition Table or GTP”.The UEFI supports disk sizes that are greater than 2 terabytes.

In addition, there are many security benefits of running UEFI on windows 10. Suppose the “Secure boots” protect the pre-boot process against the rootkits or boot kits.

Other UEFI based on security features include “device guard”, “credential guard”, and “biometric authentication”. Other features of UEFI include faster “startup time”, “shutdown times”, “stop times”, and “resuming times”.

What is Legacy BIOS?

The basic purpose of legacy boot is to start up the hardware devices. Moreover, it contains numerous installed storage devices like Optical Device Drives, Floppy Disk Drives, Hard Disk Drives, etc.

The “UEFI” provides the traditional “Blue Mode”.

Now move on to the difference between “UEFI” and “Legacy Boot”

Difference Between UEFI and Legacy BIOS

The “Legacy” BIOS and the “UEFI” is the same at a basic level (Booting process). Still, at the deeper level, the UEFI offers more functionalities. However, UEFI is the successor of BIOS as it offers additional functionalities.

The below table describes the difference between UEFI and Legacy based on the following terms and conditions:

ObjectiveIt is the next-generation interface botting process between the operating system and the platform firmware.It is the booting process used by the “BIOS” firmware.
User-InterfaceIt provides the “Graphical User Interface” where the user can use the mouse.It offers the traditional “Blue Mode” interface where the user can only use the keyboard.
LanguageIt is written in a “high-level” language “C” programming language as it allows the user to easily update or fix the bugs.It is written in a “low-level” language that depends on processor architecture-specific.
Changing or UpdatingUpdating the UEFI is easy as it does not deals with the complexities of hardware.Its updation is more complex than the UEFI.
User-FriendlyIt is more user-friendly as it runs 32-bit or 64-bit mode.It runs on only the 16-bit mode that’s why only keyboard usage is allowed init.
Partition SchemesUses the “GPT” (GUID partition table)to record hard drive data and partitions.Legacy uses the “MBR” (Master Boot Record) partition scheme.
SecurityUEFI offers security features that prevent malware from infecting a system at the start-up time.The Legacy boot does not provide security features.
Bootable StorageUEFI supports up to 9 ZEtabyte drive size or storage device that is enough at the server level.Legacy BIOS supports the 2.2 Terabyte drive size, which is OK at the consumer level.
Booting TimeBooting time of the UEFI is faster as it is faster to resume the system from sleep mode.It takes much time compared to UEFI.

That’s all about the difference between UEFI and Legacy.


UEFI,being a modern boot mechanism, has overcome the deficiencies of BIOS and thus is intended to replace it. On the other hand, the legacy boot exercises the BIOS firmware. UEFI has overcome the limitations of BIOS, and it is platform-dependent and offers a large variety of functionalities compared to Legacy BIOS. This guide illustrated a deep insight into UEFI and Legacy boot and the difference between them.