Is converting MDB to psql 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 MDB data keep its types in psql?

Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real psql 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.

Convert MDB to psql

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

1Upload your file

Click to upload or drag and drop

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

2Choose target format

How your data is typed in psql

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

Your data	psql type
Whole number	BIGINT
Decimal (money)	NUMERIC(10,2)
Floating point	DOUBLE PRECISION
True / false	BOOLEAN
Date	DATE
Date and time	TIMESTAMP
Short text	TEXT
Long text	TEXT
Binary data	BYTEA

Working from an .mdb file

An .mdb file is Jet 4, the engine Access used up to 2003. It is the format most likely to be sitting on a share drive with no copy of Access left in the building to open it - which is the situation this converter exists for.

→Jet 4 caps a database at 2 GB and a table at 255 columns, which is why an .mdb that has outgrown its purpose is usually a migration rather than a rewrite.
→There is no companion file to hunt for. A .ldb sitting beside the database is only a lock file from whoever last had it open, and nothing in it is needed - upload the .mdb on its own.
→Every table is read into memory in one pass before anything is written out, which is affordable only because the free upload is capped at 10 MB; a full-size Jet database would not be.

Running the script through psql

psql is PostgreSQL's command-line client rather than the database itself, and the script is written to be fed straight into it. Everything here is about the tool you run, not about the server you run it against.

→From inside a session already open, \i dump.sql runs the file without leaving the prompt. The script contains no backslash meta-commands of its own, so nothing in it can collide with yours.
→There is no BEGIN and no COMMIT anywhere in the file. Statements commit as they go, so a failure halfway leaves the tables already created: pass -1 to wrap the whole load in a single transaction, or -v ON_ERROR_STOP=1 to stop at the first error instead of carrying on past it.
→The script switches standard_conforming_strings on itself instead of trusting the server default, so it behaves identically against a session that has been moved off it.
→It sets client_encoding to UTF8 for the same reason. The file is written as UTF-8 with nothing to announce that, and psql would otherwise decode it using whatever the client locale says.

Reading MDB

→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 psql

→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 MDB to psql 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 MDB data keep its types in psql?: Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real psql 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.