Free online DB to MDB converter

A legacy Microsoft Access application may require an .mdb database instead of a file named .db. Conversion depends on the database engine inside the source file, because .db is an extension used by unrelated database formats.

What a DB file can contain

.db is not a single database format. It is commonly used for SQLite databases created by desktop applications, mobile software, browser components, inventory tools, and other programs that store local data; it is also used by Berkeley DB and proprietary application databases.

A SQLite database is a self-contained file that can contain tables, indexes, views, triggers, and data. Microsoft Access cannot open SQLite files directly. Other .db files may be key-value stores, encrypted application data, or non-relational databases, which cannot be converted to Access without an export feature or a compatible driver.

Identify the source before conversion. On macOS or Linux, run file source.db; SQLite files are normally identified as SQLite 3. If SQLite is installed, run sqlite3 source.db ".tables" to confirm that it opens and lists tables. If these checks fail, locate the application that created the file and use its database export function or vendor-supported driver.

A file identified as a Microsoft Jet database may already be an MDB file with the wrong extension. Back up the file, rename a copy to source.mdb, and test that copy in Microsoft Access.

What the MDB format provides

.mdb is the legacy Microsoft Access database format based on the Microsoft Jet database engine. It was the standard format for Access 2003 and earlier and remains supported by newer desktop versions of Access.

An MDB file can store Access tables, queries, indexes, relationships, forms, reports, macros, and VBA modules. It is required by some Jet-based applications and older Access deployments; newer Access databases normally use .accdb.

An MDB file has a 2 GB maximum size, including internal database objects. It cannot use newer ACCDB-only features such as attachment fields, multivalued fields, data macros, and newer encryption capabilities.

Convert a SQLite DB file to MDB

If the source is SQLite, use the converter on 101convert.com when it recognizes the uploaded database, then open the resulting .mdb in Access and verify the data. For local conversion or databases requiring controlled field mapping, import through a SQLite ODBC driver.

1. Make a copy of source.db; do not modify the only source copy.
2. Confirm that the file is SQLite, for example with sqlite3 source.db ".tables".
3. Install a SQLite ODBC driver that matches the architecture of Microsoft Access. 32-bit Access requires a 32-bit driver; 64-bit Access requires a 64-bit driver.
4. Create an ODBC data source that points to source.db. Use the ODBC Data Sources administration tool matching the driver architecture.
5. In Access, create a blank database, then save it as an MDB through File → Save As → Access Database 2002–2003 (*.mdb). The wording varies between Access releases.
6. Choose External Data → New Data Source → From Other Sources → ODBC Database, select the option to import source data into the current database, and select the SQLite data source.
7. Select the required tables. Import rather than link them if the MDB must work without the original SQLite file and ODBC driver.
8. Set primary keys, field types, indexes, and relationships after import. Check row counts and sample records before using the MDB in another application.

If the original program can export tables as CSV, create the MDB first and import each file through External Data → New Data Source → From File → Text File. Set delimiters, text encoding, column types, and primary keys during import; recreate relationships only after all tables are present.

Data and compatibility checks

SQLite uses flexible typing, while Access fields use defined types. A SQLite column containing a mix of numbers, dates, and text can be imported with an unsuitable Access type, so inspect date, currency, Boolean, and identifier fields before finalizing the database.

SQLite views, triggers, custom functions, application settings, user accounts, and application-specific metadata do not automatically become Access queries, forms, macros, or VBA code. A data conversion usually transfers tables and some schema only.

Foreign keys and indexes may not become Access relationships and indexes. Create or verify primary keys first, then define relationships through Database Tools → Relationships. Rename fields or tables that conflict with Access reserved words such as Date, User, or Value.

Encrypted, password-protected, corrupted, or proprietary .db files require the original application's credentials, export facility, or database driver. Large binary objects can increase the MDB size rapidly, and a source database near 2 GB cannot be stored in a single MDB file.