Access ACCDB files

Which conversion do you need?

• ACCDB to Excel for reading, sorting and sharing: one sheet per table, real dates and numbers.
• ACCDB to CSV for importing the data elsewhere, or for a database too big for one workbook: choose it above. You get one ZIP with a UTF-8 CSV per table, and a comma, semicolon or tab between fields. The files are written the same way as on MDB to CSV, which describes them line by line.
• An older .mdb file? It converts here too, or see MDB files.

What an ACCDB file is

Access 2007 replaced the old .mdb with .accdb, and the Jet engine with its successor, ACE. An .accdb is still one file holding the tables and everything built on them: queries, forms, reports, macros and modules. Every Access since, including the one in Microsoft 365, starts new databases in this format, so an Access file made after 2007 is most likely an .accdb.

While a database is open, Access keeps a small .laccdb lock file beside it. That file holds no data; the .accdb is the one to convert.

What the format added

Access 2007 brought attachment fields, which keep whole files inside a record; multi-value fields, which hold a short list in one field; rich formatting for long text; and encryption with a password. Access 2010 added calculated fields and a stronger default encryption. Later releases added the Large Number and Date/Time Extended types.

A spreadsheet has no exact place for several of these. ACCDB to Excel lists what each one becomes. In short, attachments come through as file names while the files stay in the database, and Large Number values arrive as text so that no digit is lost.

Versions we test

Access writes a layout version into the file, and a newer Access often saves in an older layout, so the year a file was made doesn't always match. Our 17 ACCDB test databases cover three layouts: 8 in the 2007 layout, 7 in 2010's and 2 in 2016's. Among them are files with attachments, Large Number fields and encryption, and each one is converted to Excel and to CSV.

Encryption

Encrypt with Password scrambles every page of an .accdb, so nothing in it can be read without the password. Access 2007 used RC4 for this, and Access 2010 moved the default to AES. The AES kind is in our test databases. The library we read with also handles RC4, but no RC4 file is in our tests yet, and a few rarer settings aren't supported.

Drop an encrypted file above and its row asks for the password, which is used in this tab only. The steps, and what to do when a file won't unlock, are on ACCDB to Excel.