CSV Validator
Paste or upload CSV data to check for inconsistent columns, quoting errors, empty headers, and duplicate column names.
100% client-side · no upload
How to use
- Paste your CSV data into the textarea.
- Select the delimiter and whether the first row is a header.
- Click Validate CSV to see a summary and a list of any issues found.
Related file tools
- CSV to JSON — convert validated CSV to JSON
- File Extension List — look up CSV MIME type and programs
- MIME Type Lookup — find content-type for data files
よくある質問
- Is this CSV validator free?
- Yes, completely free with no signup and no usage limits.
- Does my data leave my device?
- No. All validation runs in JavaScript inside your browser. Nothing is sent to any server.
- Does it work on mobile?
- Yes. The tool is mobile-first and works on iPhone Safari and Android Chrome.