Free online MDB to JSON converter

Source format: MDB

MDB is a Microsoft Access database file format used by older versions of Microsoft Access. It stores tables, queries, forms, reports, macros, and other database objects in a single file. MDB files are common in legacy business systems, small office databases, and older desktop applications that were built before the newer ACCDB format became standard.

People typically convert MDB files when they need to extract data, integrate it with modern tools, or move information into systems that prefer structured text formats such as JSON.

Target format: JSON

JSON (JavaScript Object Notation) is a lightweight, text-based data format used for exchanging structured data. It is widely supported by web applications, APIs, scripting languages, databases, and data-processing tools. JSON is easy to read, easy to parse, and well suited for representing records, arrays, and nested objects.

The main advantages of JSON are portability, human readability, and broad compatibility with modern software. It is especially useful when database rows need to be consumed by applications, imported into analytics tools, or transferred between systems.

How to convert MDB to JSON

The best approach depends on whether you want a one-time export or a repeatable workflow. For most users, the simplest method is to open the MDB file in Microsoft Access or a compatible database tool, export the table data to a structured intermediate format, and then convert that data to JSON. If you need a direct conversion, command-line tools and scripting are often the most reliable.

Method 1: Use Microsoft Access and a script

1. Open the MDB file in Microsoft Access.
2. Identify the table or query you want to export.
3. Export the data to CSV or XML using External Data → Export.
4. Convert the exported file to JSON with a script in Python, JavaScript, or another language.

This method is practical because Access handles the legacy MDB structure well, while the script gives you full control over field names, arrays, and nested objects.

Method 2: Use Python for direct extraction

If you want a direct MDB-to-JSON workflow, Python is a strong choice. Install a library that can read Access databases, such as pyodbc with the Microsoft Access ODBC driver or pypyodbc on supported systems. Then query the table and write the results as JSON.

Typical workflow:

1. Install the required driver and Python package.
2. Connect to the MDB file.
3. Run a SQL query against the table.
4. Serialize the returned rows to JSON.

Example conceptually: read each row as a dictionary, then save the list of dictionaries to output.json.

Method 3: Use LibreOffice Base or another database tool

Some database tools can open MDB files directly or through drivers. After opening the database, export the table data and convert it to JSON using a data-processing tool or script. This is useful if you prefer a graphical interface and only need occasional conversions.

Online conversion on 101convert.com

You can also convert the file on 101convert.com for free, without installing any software. This is convenient for quick conversions when you do not want to set up database drivers or scripts.

Quality, compatibility, and limitations

MDB is a database container, not a single flat table, so conversion to JSON is only straightforward when you choose specific tables or queries. Forms, reports, macros, and relationships do not map directly to JSON and are usually not preserved.

Be aware that data types may change during conversion. Dates, currency values, memo fields, and null values need careful handling so the JSON output remains accurate and usable. Large databases may also require splitting into multiple JSON files or exporting one table at a time.

If the MDB file is password-protected, encrypted, or uses unsupported Access features, you may need the original application or credentials before conversion is possible. For best results, export clean table data and verify the JSON output in a validator or by loading it into your target application.