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I'd like to know how to read a partition table to find out useful information such has how many partitions are on the drive, the size of the partitions and things like its starting and ending LBA addresses.

How would you figure these things out with the output below?

enter image description here

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I think the first part of that is a bootstrap loader. – Daniel R Hicks Nov 6 '11 at 20:24
Yeah, this is from the MBR. How did you know though? – 에이바 Nov 6 '11 at 20:26
It just looks like x86 instruction opcodes. I unfortunately don't know the opcodes well enough to tell for sure where the boot loader ends. The data starting at 1C0 looks like it might be partition data or some such, with possibly the data starting at 1A0 or 1B0 being a "header" for the table. – Daniel R Hicks Nov 6 '11 at 20:37
But maybe this will give you some clues. – Daniel R Hicks Nov 6 '11 at 20:39
Well, I can't spot x86 opcodes on sight but text like "Hard Disk Read Error" or "Non system disk or disk error" is a dead giveaway. – LawrenceC Dec 27 '11 at 1:28
up vote 4 down vote accepted

It's been a few years since I've had to parse the MBR, and I honestly wouldn't be as much help as this article.

That article will talk about the structure of the MBR. It'll tell you, for example, that the first 440 bytes are the "code area". The "table of primary partitions" (which is another structure within the MBR) is the area you're probably looking for, it's located 0x1BE bytes into the disk. It can contain at most 4 partition entries that are 16 bytes each.

From your snapshot above, the "table of primary partitions" starts at the last 2 bytes of the ox1B0 line (the bytes 0x8001). The 0x80 indicates that the first partition is "bootable" ( this is discussion is in the "disk partitioning" section of that article-- it also has the structure for each partition record).

You can continue to parse out the other partitions like that.

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The partition table will contain a code to identify the partition type.

Hexadecimal codes for partition types:

00 NO-Partition empty partition-table entry

01 DOS DOS 12-bit FAT

02 XENIX root file system

03 XENIX /usr file system (obsolete)

04 DOS 16-bit FAT (up to 32M)

05 Extended DOS 3.3+ extended partition

06 DOS 3.31+ Large File System (16-bit FAT, over 32M)

07 Advanced Unix


07 OS/2 HPFS

07 WindowsNT NTFS

08 OS/2 (v1.0-1.3 only)

08 AIX bootable partition, SplitDrive

08 Commodore Commodore DOS

08 DELL DELL partition spanning multiple drives

09 Coherent Coherent filesystem

09 AIX AIX data partition


0A Coherent Coherent swap partition

0A OS/2 OS/2 Boot Manager

0B Windows95 with 32-bit FAT

0C Windows95 with 32-bit FAT (using LBA-mode INT 13 extensions)

0E VFAT logical-block-addressable VFAT (same as 06h but using LBA)

0F Extended LBA Extended partition (same as 05h but using LBA)


11 FAT12 OS/2 Boot Manager hidden 12-bit FAT partition

12 Compaq Compaq Diagnostics partition

14 FAT16 OS/2 Boot Manager hidden sub-32M 16-bit FAT partition

16 FAT16 OS/2 Boot Manager hidden over-32M 16-bit FAT partition

17 OS/2 OS/2 Boot Manager hidden HPFS partition

17 NTFS hidden NTFS partition

18 ASTSuspend AST special Windows swap file ("Zero-Volt Suspend" partition)

19 Willowtech Willowtech Photon coS

1B Windows hidden Windows95 FAT32 partition

1C Windows hidden Windows95 FAT32 partition (LBA-mode)

1E Windows hidden LBA VFAT partition

20 Willowsoft Willowsoft Overture File System (OFS1)

21 [reserved] officially listed as reserved

21 FSo2

23 [reserved] officially listed as reserved

24 NEC MS-DOS 3.x

26 [reserved] officially listed as reserved

31 [reserved] officially listed as reserved

33 [reserved] officially listed as reserved

34 [reserved] officially listed as reserved

36 [reserved] officially listed as reserved

38 Theos

3C PowerQuest PartitionMagic recovery partition

40 VENIX 80286

41 Personal RISC Boot

41 PowerPC boot partition

42 SFS(Secure File System) by Peter Gutmann

45 EUMEL/Elan

46 EUMEL/Elan

47 EUMEL/Elan

48 EUMEL/Elan

4F Oberon Oberon boot/data partition

50 OnTrack Disk Manager, read-only partition

51 OnTrack Disk Manager, read/write partition


52 CP/M

52 Microport System V/386

53 OnTrack Disk Manager, write-only partition???

54 OnTrack Disk Manager (DDO)

55 EZ-Drive EZ-Drive (see also INT 13/AH=FFh"EZ-Drive")

56 GoldenBow GoldenBow VFeature

5C Priam Priam EDISK

61 SpeedStor

63 UnixSysV Unix SysV/386, 386/ix

63 Mach Mach, MtXinu BSD 4.3 on Mach


64 Novell Novell NetWare 286

64 SpeedStore SpeedStore

65 Novell NetWare (3.11)

67 Novell

68 Novell

69 Novell NSS Volume

70 DiskSecure DiskSecure Multi-Boot

71 [reserved] officially listed as reserved

73 [reserved] officially listed as reserved

74 [reserved] officially listed as reserved


76 [reserved] officially listed as reserved

7E F.I.X. F.I.X.

80 Minix Minix v1.1 - 1.4a

81 Minix Minix v1.4b+

81 Linux Linux

81 Mitac Mitac Advanced Disk Manager

82 Linux/Swap Linux Swap partition

82 Prime Prime

82 Solaris Solaris (Unix)

83 Linux Linux native file system (ext2fs/xiafs)

84 DOS OS/2-renumbered type 04h partition (hiding DOS C: drive)

85 Linux Linux EXT

86 FAT16 FAT16 volume/stripe set (Windows NT)

87 HPFS HPFS Fault-Tolerant mirrored partition

87 NTFS NTFS volume/stripe set

93 Amoeba Amoeba file system

94 Amoeba Amoeba bad block table

98 Datalight Datalight ROM-DOS SuperBoot

99 Mylex Mylex EISA SCSI

A0 Phoenix Phoenix NoteBIOS Power Management "Save-to-Disk" partition

A1 [reserved] officially listed as reserved

A3 [reserved] officially listed as reserved

A4 [reserved] officially listed as reserved

A5 FreeBSD FreeBSD, BSD/386

A6 OpenBSD OpenBSD

A9 NetBSD NetBSD (

B1 [reserved] officially listed as reserved

B3 [reserved] officially listed as reserved

B4 [reserved] officially listed as reserved

B6 [reserved] officially listed as reserved

B6 Windows Windows NT mirror set (master), FAT16 file system

B7 BSDI BSDI file system (secondarily swap)

B7 Windows Windows NT mirror set (master), NTFS file system

B8 BSDI BSDI swap partition (secondarily file system)

BE Solaris Solaris boot partition


C0 DR-DOS DR DOS/DR-DOS/Novell DOS secured partition

C1 DR-DOS6.0 DR DOS 6.0 LOGIN.EXE-secured 12-bit FAT partition

C4 DR-DOS6.0 DR DOS 6.0 LOGIN.EXE-secured 16-bit FAT partition

C6 DR-DOS6.0 DR DOS 6.0 LOGIN.EXE-secured Huge partition

C6 corrupted corrupted FAT16 volume/stripe set (Windows NT)

C6 Windows Windows NT mirror set (slave), FAT16 file system

C7 Syrinx Syrinx Boot

C7 corrupted corrupted NTFS volume/stripe set

C7 Windows Windows NT mirror set (slave), NTFS file system

CB DR-DOS Reserved for DR DOS/DR-DOS/OpenDOS secured FAT32

CC DR-DOS Reserved for DR DOS/DR-DOS secured FAT32 (LBA)

CE DR-DOS Reserved for DR DOS/DR-DOS secured FAT16 (LBA)

D0 Multiuser Multiuser DOS secured FAT12

D1 Old-FAT12 Old Multiuser DOS secured FAT12

D4 Old-FAT16 Old Multiuser DOS secured FAT16 (<= 32M)

D5 Old-Ext Old Multiuser DOS secured extended partition

D6 Old-FAT16 Old Multiuser DOS secured FAT16 (> 32M)

D8 CP/M-86 CP/M-86

DB CP/M CP/M, Concurrent CP/M, Concurrent DOS

DB CTOS CTOS (Convergent Technologies OS)

E1 SpeedStor SpeedStor 12-bit FAT extended partition

E2 DOS DOS read-only (Florian Painke's XFDISK 1.0.4)

E3 DOS DOS read-only

E3 Storage Storage Dimensions

E4 SpeedStor SpeedStor 16-bit FAT extended partition

E5 [reserved] officially listed as reserved

E6 [reserved] officially listed as reserved


F1 Storage Storage Dimensions

F2 DOS DOS 3.3+ secondary partition

F3 [reserved] officially listed as reserved

F4 SpeedStor SpeedStor

F4 Storage Storage Dimensions

F5 Prologue Prologue

F6 [reserved] officially listed as reserved

FB VMWARE vmware partition

FE LANstep LANstep

FE PS/2-IML IBM PS/2 IML (Initial Microcode Load) partition

FF Xenix Xenix bad block table

FM VMware VMware raw partition

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