Convert MS Access to Postgres

Upload a .mdb or .accdb or .mde file and get back a Postgres SQL script you can load straight into your database. Types are preserved rather than flattened to text. Free, no registration, up to 10MB.

Click to upload or drag and drop

CSV, Excel, SQLite, SQL, DBF (max 10 MB)

How your data is typed in Postgres

Generated from the converter's own Postgres type mapping — this is what it actually emits, not an example.

Your dataPostgres type
Whole numberBIGINT
Decimal (money)NUMERIC(10,2)
Floating pointDOUBLE PRECISION
True / falseBOOLEAN
DateDATE
Date and timeTIMESTAMP
Short textTEXT
Long textTEXT
Binary dataBYTEA

Working from an Access database

An Access file is an application as much as a database: tables, but also queries, forms, reports, macros and VBA modules. Only one of those is data, and only that one is something a conversion can carry anywhere else.

  • The tables convert. Saved queries, forms, reports, macros and modules are not data and do not appear in the output - re-create a query as a view in the target if you need it.
  • Access types map to fixed shapes: Currency to DECIMAL(19,4), matching Access's own four fixed decimal places, Decimal to DECIMAL(18,6), Long Integer to a 32-bit integer, Byte and Integer to 16-bit, Memo and Hyperlink to text, OLE and Binary to a blob.
  • If the file cannot be opened at all - a database password, or real damage - the conversion stops with the underlying tool's own error instead of handing you a partial result.

The oldest PostgreSQL this loads into

Postgres is the informal spelling and the one most people type. Since the name says nothing about a version, the useful question for this page is which server releases the generated script runs on, and that is decided by the newest piece of syntax in it.

  • The identity clause on auto-increment columns is the newest thing in the file, and it arrived in release 10. That is the floor for loading the script unedited.
  • Everything else is far older: the hex escape the script uses for binary values has been accepted since 9.0, and jsonb, which is what a JSON column is declared as, since 9.4.
  • On a server below the floor the script still loads if you delete the identity clauses by hand. The columns keep every value they were given, because each INSERT names them explicitly; they simply stop assigning new ones.

Reading MS Access

  • Dates are exported in ISO form, avoiding the ambiguous 12/02/21 that Access tools produce by default.
  • NULL and the empty string stay distinct.
  • Access can hold dates outside the range it can represent. Those become NULL and the conversion tells you, rather than dropping them silently.
  • Requires mdbtools on the server; if it is unavailable you get a clear error rather than a partial conversion.

Writing Postgres

  • Backslashes are left alone, because PostgreSQL treats them as ordinary characters — doubling them would corrupt every Windows path.
  • Auto-increment columns become GENERATED BY DEFAULT AS IDENTITY.
  • Binary data is written as bytea, and identifiers respect the 63-character limit.

What you get

A ZIP containing dump.sql, plus a README with the exact command to load it. If anything about your data needed a judgement call, a _warnings.txt explains it.

Load this dump into PostgreSQL:

  psql -U USER -d DATABASE -f dump.sql

Create the database first if it does not exist:

  createdb -U USER DATABASE

Questions

Is converting MS Access to Postgres free?
Yes. Files up to 10MB convert free with no account. There is a limit of five conversions per day per IP address.
Will my MS Access data keep its types in Postgres?
Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real Postgres types rather than everything becoming text. The mapping table above shows exactly what you get.
Do you store my file?
No. The file is written to a temporary directory, converted, and the directory is deleted as soon as your download has been sent.

This conversion, under other names

Convert MS Access to something else

Convert something else to Postgres