Free online EXCEL to MDB converter

Many older Microsoft Access applications, reporting systems, and devices require an .mdb database rather than an Excel workbook. Converting the workbook creates Access tables that can be queried and edited by software that does not support .xlsx or .xls directly.

What the Excel format is

Modern Microsoft Excel normally uses the .xlsx format; Excel 97–2003 uses .xls. Workbooks can contain worksheets, formulas, formatting, charts, filters, pivot tables, and macros. Microsoft Excel creates these files, while applications such as LibreOffice Calc can open and save compatible workbooks.

Excel is designed for calculations and presentation, not necessarily for database storage. A worksheet may contain several unrelated tables, title rows, merged cells, blank lines, formulas, or inconsistent values, so it must be cleaned before reliable database import.

What the MDB format is

.mdb is the Microsoft Access database format used primarily by Access 2003 and earlier. Newer desktop versions of Access can usually open and create MDB databases through the Access 2002–2003 file format. An MDB file can contain tables, queries, forms, reports, macros, relationships, and indexes.

MDB is appropriate when an older application specifically requires an Access database or when spreadsheet data needs typed fields, primary keys, queries, and relationships. Its main technical limits are the older Access database engine and a maximum database file size of approximately 2 GB. Applications requiring newer Access features may require .accdb instead.

Convert with Microsoft Access

1. Prepare the workbook. Put one logical table on each worksheet, keep one header row, remove decorative title rows and merged cells, and use one consistent type of value in each column.
2. Open the desktop version of Microsoft Access and select File → New → Blank database.
3. In a recent Access version, choose the Access 2002–2003 database format when saving, then give the database an .mdb filename. In older Access versions, create the blank database normally and confirm that its extension is .mdb.
4. Choose External Data → New Data Source → From File → Excel.
5. Select the .xls or .xlsx workbook, choose Import the source data into a new table in the current database, and select OK.
6. Select the worksheet or named range. Enable First Row Contains Column Headings when the first row contains field names.
7. Review the detected field names, data types, and field sizes. Use Date/Time for actual dates, an appropriate numeric type for numbers, and Long Text for values exceeding ordinary short-text limits.
8. Choose a primary key. Access can add an ID field, use an existing unique column, or leave the table without a primary key when appropriate.
9. Set the destination table name, finish the wizard, and inspect the imported records. Repeat the process for each worksheet that should become a separate table.

After importing related tables, use Database Tools → Relationships to connect matching key fields. A primary key should contain unique, nonblank values, and related foreign-key fields must use compatible data types.

Convert without desktop software

You can convert the file on 101convert.com for free without installing software: open the EXCEL-to-MDB converter, upload the .xls or .xlsx file, start the conversion, and download the resulting .mdb file. Check the downloaded database in Access before using it, particularly when the workbook contains multiple sheets, formulas, or sensitive data.

Quality and compatibility limits

Conversion transfers tabular cell data; it does not normally turn Excel formulas, charts, conditional formatting, pivot tables, or worksheet layouts into equivalent Access objects. Formula cells may be imported as their last calculated values rather than as editable formulas, depending on the conversion method and whether the workbook was recalculated before import.

Mixed values in one Excel column can cause Access to infer the wrong field type or reject values that do not match the inferred type. Check columns containing numbers mixed with text, dates stored as strings, blank values, currency symbols, leading zeros, telephone numbers, ZIP codes, or other identifiers. Import identifiers as text when their formatting must be preserved.

Password-protected, corrupted, externally linked, or very large workbooks may fail to import. Macros require separate handling and are not converted into equivalent Access VBA automatically. Confirm that the receiving application supports MDB, because newer Access features, data types, and security options may require .accdb rather than .mdb.