dataeng.tools

Schema diff — compare two files’ columns

Drop two files (Parquet, Avro, CSV, TSV, JSON or JSONL) to see how their schemas differ — which columns were added or removed and which changed type. Perfect for catching schema drift between two versions of a table. It all runs in your browser; neither file is uploaded.

Drop a file or click to browse

First file (before)

Drop a file or click to browse

Second file (after)

Frequently asked questions

What does the diff show?
Column-level changes between two files' schemas: columns added, columns removed, and columns whose type changed. It's a schema diff, not a row-by-row data diff.
What is schema drift?
When a dataset's shape changes between versions — a column renamed, dropped, added or retyped — often silently breaking a downstream pipeline. Diffing two snapshots catches it before it ships.
Which formats can I compare?
Any mix of Parquet, Avro, CSV, TSV, JSON, JSONL and Excel — the two files don't have to be the same format.
Are the files uploaded?
No. Both files are read in your browser with DuckDB-WASM; only their schemas are compared, and neither file leaves your device.

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