Structured data
CSV Viewer and Cleaner
Inspect and clean a CSV table without uploading it to a spreadsheet service.
Processed locally. Your input and output are never uploaded.
Tool overview
A local CSV cleanup workspace
CSV Viewer and Cleaner always parses and transforms data in a local Web Worker. It supports delimiter detection, paginated preview, selected and reordered columns, header renaming, empty and duplicate row removal, cell trimming, column-scoped find and replace, filtering, sorting, and CSV export.
Inspect and reshape local tabular exports
- Inspect an unfamiliar CSV export
- Remove blank or duplicate records
- Reorder and rename report columns
- Filter and replace values in chosen columns
Clean a CSV in the worker-backed table
- Paste CSV or open a local file up to 10 MB.
- Confirm the detected delimiter.
- Enter optional column and cleanup rules.
- Review the paginated preview and download to save changes.
Columns, filters, replacement, sorting, and output
- Column lists use existing header names separated by commas.
- Rename mappings use old:new pairs.
- Find and replace can target selected columns or all columns.
- The preview shows up to 5,000 rows; output retains every accepted row.
Remove duplicate and empty CSV rows
Before
name,city Ana , Jakarta Ana , Jakarta ,
After
name,city Ana,Jakarta
Browser memory, preview, column, and file limits
- Files larger than 10 MB and tables wider than 200 columns are rejected gracefully.
- Preview is capped at 5,000 rows for browser responsiveness.
- Changes remain unsaved until the cleaned CSV is downloaded.
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Questions
CSV Viewer and Cleaner FAQ
Does opening a file upload it?
No. The File API reads it only into the current browser tab.
Why is the preview paginated?
Rendering a small page keeps keyboard navigation and browser performance predictable.