Validate CSV Files Online

What does the CSV validation report show?

For each column: detected data type, total row count, null count, null percentage, and distinct value count. It gives you a fast overview of data quality before loading into a database or pipeline.

Does validating a CSV file modify it?

No. Validation is read-only — it generates a report in your browser and does not modify or download anything.

What should I look for in the CSV validation results?

High null counts may indicate missing data or parsing errors. Unexpectedly low distinct counts can reveal collapsed or corrupted columns. Columns detected as a mixed type often contain formatting inconsistencies.

Is my data private?

Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.

What is the maximum file size?

The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.