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Optimize & Repair · browser workspace

CSV Diagnostic

Find delimiter, encoding, header, row-shape, type, and data-quality problems before importing a CSV. Process locally in your browser with HappyCSV.

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How to use this tool

Quick start

Built for understanding why a csv import fails before applying a repair.

Everything runs in your browser, so you can test the workflow with sample data when available before using production files.

Output: A JSON diagnostic report with actionable data-quality findings.

  1. 1Upload the problematic file.
  2. 2Review delimiter, encoding, headers, row-shape, and type findings.
  3. 3Use the recommended repair tool and re-check the result.

How to CSV Diagnostic

  1. 1Upload the problematic file.
  2. 2Review delimiter, encoding, headers, row-shape, and type findings.
  3. 3Use the recommended repair tool and re-check the result.

Why Use This Tool?

  • ✓Find delimiter, encoding, header, row-shape, type, and data-quality problems before importing a CSV.
  • ✓A JSON diagnostic report with actionable data-quality findings.
  • ✓Files are processed locally in this browser.
  • ✓Keep the source file and review the result before importing it elsewhere.

Frequently Asked Questions

What does this tool support?

A JSON diagnostic report with actionable data-quality findings.

What are the processing limits?

Up to 100 MB per CSV, 20 MB per complex document; 250,000 rows, 1,000 columns, 2 million cells, and 128 MB output. Jobs stop after two minutes. Large files may need splitting.

Are my files uploaded?

No. File processing stays in your browser. Files are not automatically saved for the next visit.

Can I process multiple files?

This tool processes one file at a time.

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