What is a .MBR file?
MBR is the classic first sector of a disk, holding the partition table and boot code.
- Did you know
- The MBR scheme arrived in 1983 with PC DOS 2.0 and the IBM PC XT, and its 32-bit sector count caps disks at 2 TB.
- The 512-byte record splits into 446 bytes of boot code, a 64-byte partition table and a two-byte end signature.
- Because the table holds only four entries, classic MBR disks are limited to four primary partitions, a limit GPT removes.
- What Analyser reads
- Inspect virtual-machine descriptors (VMware .vmx, VirtualBox .vbox, OVF/OVA), disc images (Nero .nrg, Alcohol .mds/.mdf, CloneCD), embedded firmware (Intel HEX, Motorola S-record, UF2, ELF/AXF, Device Tree Blobs, U-Boot uImage), partition tables (MBR/GPT with GUIDs), Linux filesystem superblocks (ext2/3/4, SquashFS, cramfs, romfs) and Windows imaging (WIM/ESD) - reading headers directly, no upload. The two generic suffixes are handled on their bytes rather than their name: a .bin opens in the raw-binary inspector (magic-byte guess, entropy profile, hex and ASCII dump) and names itself when the signature proves a raw BIN/CUE disc image or a Mega Drive cartridge dump, while a .out is read as either the ELF executable a compiler left behind or the plain-text log a batch job dumped. Either one is re-routed automatically when its bytes turn out to be a real format.
- Depth of analysis
- .MBR is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .MBR file
- Drag a .MBR file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.