.mdb

What is a .mdb file?

MDB is the legacy Microsoft Access database format (pre-2007) — still found in older business applications and government systems.

Use caution
Type Data
By Microsoft
MIME application/x-msaccess

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What is it

MDB is Microsoft Access's original database format, used from Access 97 through Access 2003. It stores tables, queries, forms, reports, macros, and VBA code in a single binary file based on the Jet Database Engine. Millions of small business applications, government databases, and departmental tools were built on MDB files.

The format was replaced by ACCDB in Access 2007, but MDB files persist stubbornly. Legacy applications, regulatory archives, and organisations that never upgraded still run on MDB databases. Some are mission-critical systems maintained by a single person who retired years ago.

Microsoft Access (paid) opens MDB files natively. For free access, MDB Viewer Plus (Windows) reads MDB without Access installed. LibreOffice Base has partial MDB support. For programmatic access, Python's `pyodbc` or `mdbtools` (Linux/Mac) can read MDB tables. If possible, convert to ACCDB or export to SQLite/CSV for long-term preservation.

Technical details
Full Name
Microsoft Access Database
MIME Type
application/x-msaccess
Developer
Microsoft
Magic Bytes
00 01 00 00
Safety
.mdb requires caution. MDB files can contain VBA macros that execute automatically. Only open MDB files from trusted sources.
What opens it
Microsoft Access
PAID Windows
MDB Viewer Plus
FREE Windows
LibreOffice Base
FREE Windows / Mac / Linux
FAQ
How do I open an MDB file without Access?
MDB Viewer Plus (Windows, free) reads MDB files. LibreOffice Base has partial support. On Mac/Linux, mdbtools reads MDB tables from the command line. For one-time access, convert to CSV.
What's the difference between MDB and ACCDB?
ACCDB replaced MDB in Access 2007. ACCDB supports better encryption, attachment fields, multivalued fields, and the newer ACE database engine. MDB is limited to 2 GB and uses weaker security.
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