In computing, the System Management BIOS (SMBIOS) specification defines data structures (and access methods) that can be used to read management information produced by the BIOS of a computer. This eliminates the need for the operating system to probe hardware directly to discover what devices are present in the computer. The SMBIOS specification is produced by the Distributed Management Task Force (DMTF), a non-profit standards development organization. The DMTF estimates that two billion client and server systems implement SMBIOS..

SMBIOS was originally known as Desktop Management BIOS (DMIBIOS), since it interacted with the Desktop Management Interface (DMI).

History Version 1 of the Desktop Management BIOS (DMIBIOS) specification was produced by Phoenix Technologies in or before 1996.

Version 2.0 of the Desktop Management BIOS specification was released on March 6, 1996 by American Megatrends (AMI), Award Software, Dell, Intel, Phoenix Technologies, and SystemSoft Corporation. It introduced 16-bit plug-and-play functions used to access the structures from Windows 95.

The last version to be published directly by vendors was 2.3 on August 12, 1998. The authors were American Megatrends, Award Software, Compaq, Dell, Hewlett-Packard, Intel, International Business Machines (IBM), Phoenix Technologies, and SystemSoft Corporation.

Circa 1999, the Distributed Management Task Force (DMTF) took ownership of the specification. The first version published by the DMTF was 2.3.1 on March 16, 1999. At approximately the same time Microsoft started to require that OEMs and BIOS vendors support the interface/data-set in order to have Microsoft certification.

Version 3.0.0, introduced in February 2015, added a 64-bit entry point, which can coexist with the previously defined 32-bit entry point.

The latest version 3.9.0 was released in August 2025.

Contents The SMBIOS table consists of an entry point (two types are defined, 32-bit and 64-bit), and a variable number of structures that describe platform components and features. These structures are occasionally referred to as "tables" or "records" in third-party documentation.

Structure types As of version 3.3.0, the SMBIOS specification defines the following structure types:SMBIOS Specification, version 3.3.0, Sep 2019, https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.3.0.pdf

Type Description 0 BIOS Information 1 System Information 2 Baseboard (or Module) Information 3 System Enclosure or Chassis 4 Processor Information 5 Memory Controller Information (Obsolete) 6 Memory Module Information (Obsolete) 7 Cache Information 8 Port Connector Information 9 System Slots 10 On Board Devices Information 11 OEM Strings 12 System Configuration Options 13 BIOS Language Information 14 Group Associations 15 System Event Log 16 Physical Memory Array 17 Memory Device 18 32-Bit Memory Error Information 19 Memory Array-Mapped Address 20 Memory Device-Mapped Address 21 Built-in Pointing Device 22 Portable Battery 23 System Reset 24 Hardware Security 25 System Power Controls 26 Voltage Probe 27 Cooling Device 28 Temperature Probe 29 Electrical Current Probe 30 Out-of-Band Remote Access 31 Boot Integrity Services (BIS) Entry Point 32 System Boot Information 33 64-Bit Memory Error Information 34 Management Device 35 Management Device Component 36 Management Device Threshold Data 37 Memory Channel 38 IPMI Device Information 39 System Power Supply 40 Additional Information 41 Onboard Devices Extended Information 42 Management Controller Host Interface 43 TPM Device 44 Processor Additional Information 126 Inactive 127 End-of-Table 128–255 Available for system- and OEM- specific information 129 Intel ASF 130 Intel AMT 131 Intel Management Engine

Accessing SMBIOS data The EFI configuration table (EFI_CONFIGURATION_TABLE) contains entries pointing to the SMBIOS 2 and/or SMBIOS 3 tables.UEFI Specification, version 2.6, section 4.6 There are several ways to access the data, depending on the platform and operating system.

From UEFI In the UEFI Shell, the command can retrieve and display the SMBIOS data. One can often enter the UEFI shell by entering the system firmware settings, and then selecting the shell as a boot option (as opposed to a DVD drive or hard drive).

From Unix For Linux, FreeBSD, etc., the dmidecode utility can be used.

From Windows Microsoft specifies WMI as the preferred mechanism for accessing SMBIOS information from Microsoft Windows.SMBIOS Support in Windows, Microsoft paper, updated April 25, 2005

On Windows systems that support it (XP and later), some SMBIOS information can be viewed with either the WMIC utility with 'BIOS'/'MEMORYCHIP'/'BASEBOARD' and similar parameters, or by looking in the Windows Registry under HKLM\HARDWARE\DESCRIPTION\System.

Various software utilities can retrieve raw SMBIOS data, including AIDA64, FirmwareTablesView and SMBIOS Decoder.

Generating SMBIOS data Table and structure creation is normally up to the system firmware/BIOS. The UEFI Platform Initialization (PI) specification includes an SMBIOS protocol (EFI_SMBIOS_PROTOCOL) that allows components to submit SMBIOS structures for inclusion, and enables the producer to create the SMBIOS table for a platform.Platform Initialization Specification, volume 5, section 6, SMBIOS Protocol

Platform virtualization software can also generate SMBIOS tables for use inside VMs, for instance QEMU.QEMU version 2.12.50 User Documentation, https://qemu.weilnetz.de/doc/qemu-doc.html

If the SMBIOS data is not generated and filled correctly then the machine may behave unexpectedly. For example, a Mini PC that advertises Chassis Information | Type = Tablet may behave unexpectedly using Linux. A desktop manager like GNOME will attempt to monitor a non-existent battery and shut down the screen and network interfaces when the missing battery drops below a threshold. Additionally, if the Chassis Information | Manufacturer is not filled in correctly then work-arounds for the incorrect Type = Tablet problem cannot be applied.

See also Web-Based Enterprise Management (WBEM)

References

External links

SMBIOS Demystified, August 1, 2006, by Kiran Sanjeeva