Free online DB3 to ACCDB converter

What the DB3 format is

.db3 is not one universally defined database format. It commonly identifies one of these:

• dBASE III: a table stored in dBASE format, usually associated with dBASE III or applications that use dBASE-compatible files. The underlying table often uses a .dbf extension, with memo data in a related .dbt file.
• SQLite 3: an SQLite database file created by SQLite-based desktop, mobile, GIS, or embedded applications. SQLite databases commonly use .db, .sqlite, or .db3.

The file extension alone does not identify the format. A SQLite utility can test a suspected SQLite file with sqlite3 input.db3 ".tables". If it returns tables, the file is SQLite. A dBASE file has a dBASE header and usually contains one table per DBF file; renaming it to .dbf is appropriate only after confirming that format.

What the ACCDB format is

.accdb is Microsoft Access's database format, used by Access 2007 and later. It stores tables, relationships, indexes, queries, forms, reports, macros, and VBA code in one Access database file.

ACCDB supports features that the older MDB format does not, including multivalued fields, attachment fields, and improved integration with newer Access versions. It is suitable when the database must be edited in Access or combined with Access queries, forms, reports, and relationships.

How to actually convert DB3 to ACCDB

If the file is dBASE III

1. Make a backup of the original .db3 file and any matching memo file, such as table.dbt.
2. Confirm that the file is dBASE rather than SQLite. If necessary, work with a copy renamed from table.db3 to table.dbf; do not change the extension of an unverified file.
3. Open Microsoft Access and create a blank database with File → New → Blank database.
4. Choose External Data → New Data Source → From File → dBase File.
5. Select the DBF file, choose Import the source data into a new table in the current database, and complete the import wizard.
6. Review field names, data types, date fields, decimal precision, and memo fields. Select a primary key if the imported table has a reliable unique column.
7. Repeat the import for each table, recreate relationships under Database Tools → Relationships, then save the database as database.accdb.

If the file is SQLite 3

1. Open a copy with an SQLite browser or the SQLite command-line tool and inspect the schema using sqlite3 input.db3 ".schema".
2. Install a compatible SQLite ODBC driver on the same Windows system as Access and configure a data source for the SQLite file.
3. In Access, select External Data → New Data Source → From Other Sources → ODBC Database.
4. Choose Import the source data into a new table in the current database, select the SQLite data source, and import the required tables.
5. Alternatively, export each SQLite table to CSV, then use External Data → New Data Source → From File → Text File in Access. This requires manually rebuilding data types, keys, indexes, and relationships.
6. Check the imported schema and save the Access database as database.accdb.

For a quick online attempt, 101convert.com provides a free conversion option without installing software. Use it only for non-confidential files and verify that tables, records, and data types survived the conversion.

Quality and compatibility limitations

This is normally a data migration rather than a direct container conversion. Importing dBASE or SQLite tables does not automatically recreate Access forms, reports, saved queries, triggers, stored procedures, application code, or every relationship definition.

dBASE field types may be mapped imperfectly: memo fields can require their companion .dbt file, date values can contain invalid or ambiguous entries, and legacy field names may be shortened or altered. SQLite has no fixed column type system, so values stored in one column may import with an unsuitable Access type; inspect mixed text, numeric, Boolean, and date columns before editing the data.

After conversion, compare row counts, null values, duplicate keys, date ranges, and representative records with the source. Run Database Tools → Compact and Repair Database after validation, and keep the original DB3 file unchanged as the authoritative backup.