What validation rules are supported?

Required columns, data types, value ranges, regex patterns, and allowed values (enums).

Can I save a schema for reuse?

Yes — export the schema as JSON and reload it for future validations.

No. Everything runs locally in your browser.

Process files up to the browser memory limit.

Yes — drop multiple files and each is validated and reported separately.

Validate CSV structure, headers, data types, and required fields against a schema. Processed entirely in your browser for 100

Your files never leave your device. Processed locally. 100% private.

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Complete your task perfectly in just three straightforward steps.

Drop your CSV file.

Define expected columns, types, and required fields. Or upload a JSON schema.

Validation errors are listed with row numbers. Download a report.

Everything you need to know about the CSV Validator.

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