Convert DuckDB to SQLite
Upload a .duckdb or .ddb file and get back a SQLite file. 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 SQLite
Generated from the converter's own SQLite type mapping — this is what it actually emits, not an example.
| Your data | SQLite type |
|---|---|
| Whole number | BIGINT |
| Decimal (money) | NUMERIC(10,2) |
| Floating point | REAL |
| True / false | BOOLEAN |
| Date | DATE |
| Date and time | TIMESTAMP |
| Short text | TEXT |
| Long text | TEXT |
| Binary data | BLOB |
Working from a .duckdb file
DuckDB keeps an entire analytical database in one file, with real types behind it - decimals that are decimals, and integers wide enough to be worth checking before you move them somewhere narrower.
- →Only the main schema is read. Tables created in another schema, or in a second database attached at query time, are not part of the conversion.
- →Views in main are read as though they were tables, so a view's rows are materialised into the target rather than skipped.
- →HUGEINT is the one type with nowhere to go: no target here has a 128-bit integer, so those columns are carried across as text rather than silently truncated.
- →A DuckDB process that was killed leaves a .duckdb.wal sidecar holding everything it had not checkpointed yet. Upload the database on its own and it opens with no error and no tables at all - send the .wal file alongside it, or checkpoint before you copy the database out.
What the .sqlite file looks like inside
The output here is a real database rather than a script, so the interesting question is not how to load it but what SQLite did with the types on the way in. Its storage classes are looser than the declarations the file ends up carrying.
- →Names are carried over exactly as they were, with none of the sanitising the script targets apply: a table called Sales Report keeps its space and a column called Order ID keeps its own, so your queries have to quote them.
- →Underneath the declared types sit only five storage classes, and NUMERIC affinity - what a decimal column gets - is the loosest of them: it normalises inserted text to whatever a plain INTEGER or REAL column would hold. The precision and scale in the schema are for a human reading it, not a guarantee SQLite enforces on the bytes; the Writing notes below cover what that means for money specifically.
- →Declared type and stored type are different things here: a BOOLEAN column holds the integers 1 and 0, and a DATE column holds ISO text, because those are the storage classes SQLite actually has. Every client reads them back the same way.
Reading DuckDB
- →Types, primary keys and NOT NULL constraints are read from the database.
- →The file is opened read-only, so your upload is never modified or upgraded in place.
Writing SQLite
- →Columns get real declared types rather than everything being TEXT.
- →Primary keys and NOT NULL constraints are preserved.
- →A money column is declared NUMERIC(10,2), but that declaration does not stop SQLite’s own numeric affinity from converting the inserted value into a float once it lands, so 19.99 can come back with a rounding tail. Pick the DuckDB target instead when the exact decimal has to survive.
What you get
A ZIP containing database.sqlite. If anything about your data needed a judgement call, a _warnings.txt explains it.
Questions
- Is converting DuckDB to SQLite 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 DuckDB data keep its types in SQLite?
- Yes — that is the point. Whole numbers, decimals, dates and booleans are mapped to real SQLite 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.