CSV Cleaner & Validator

The CSV cleaner auto-detects delimiters, trims whitespace, drops empty rows, and removes duplicates so you can get a clean CSV or a quick JSON preview without opening spreadsheets. Everything runs in your browser.

1. Paste CSV: Drop your data into the input box.
2. Pick delimiter: Leave on “Auto-detect” unless you know it (comma, tab, semicolon, pipe).
3. Choose cleanup: Keep “Trim whitespace” and “Drop empty rows” on; toggle “Remove duplicates” if needed.
4. Export: Select CSV or JSON preview, then copy the output.

• Fast normalization: Fix headers and rows without opening a spreadsheet.
• Dedupe safely: Remove identical rows after trimming.
• Privacy-first: Parsing happens locally; your data stays in your browser.

Use case 1: Marketing lists

Paste lead exports, trim spaces, drop blank lines, and dedupe before uploading to your ESP.

Use case 2: Analytics snippets

Clean small data extracts from dashboards and preview as JSON for quick API mocks.

Use case 3: Dev fixtures

Normalize CSV inputs before importing into tests or seed scripts.

Basic example

Input:

 email , plan , country
 user-contact , pro , US
 user-contact , pro , US

Settings: trim, drop empty rows, dedupe = on.
Output (CSV):

email,plan,country
user-contact,pro,US

JSON preview

Same input with export = JSON → returns first 100 rows as objects:
[{ "col_1": "email", "col_2": "plan", "col_3": "country" }, ...]

Wrong delimiter detected

Manually pick the delimiter if auto-detect guesses wrong (e.g., many commas inside quoted text).

Quotes doubled

If you see doubled quotes, the source had escaped quotes; the cleaner keeps them valid. Remove extra quotes in source if they were unintended.

• Keep headers consistent; the tool does not rename columns—fix header typos before deduping.
• To remove duplicate emails regardless of case, run the email column through the lowercase tool first.
• If you only need one column, clean, then extract with the duplicate line remover.

• Encode or decode URLs in your CSV with the URL encoder.
• Format or minify JSON exports with the JSON formatter and JSON minifier.
• Compare rows from two files with the list comparer.

CSV parsing and cleaning happen locally in your browser. No data is uploaded or stored. JSON preview is generated client-side from the cleaned rows.