CSV Structure Checker
Inspect CSV field counts, empty or duplicate headers and possible spreadsheet formulas. Limits: 1 MiB UTF-8, 5,000 records, 200 fields/record, 100,000 cells and 20,000 characters/cell; display at most 200 findings.
A QUICK WALKTHROUGH
How to use this tool
- Paste input, choose options, then analyze and review the report.
Scope and limits
Choose comma, tab or semicolon and whether the first record is a header. Full-field quotes, doubled quotes and multiline fields are supported. Accepts LF/CRLF/CR and leading BOM. Invalid quoting stops the report. Compare width with the first record; headers are trimmed and compared case-sensitively. A value starting with =, +, - or @ after whitespace triggers a formula warning, including negative numbers. This conservative heuristic may miss application-specific behavior. It neither sanitizes data nor certifies safety or CSV compliance.
Processed only in your browser; input is not uploaded or saved.
Inspect CSV field counts, empty or duplicate headers and possible spreadsheet formulas. Limits: 1 MiB UTF-8, 5,000 records, 200 fields/record, 100,000 cells and 20,000 characters/cell; display at most 200 findings.
GOOD TO KNOW
Common questions
Scope and limits
Choose comma, tab or semicolon and whether the first record is a header. Full-field quotes, doubled quotes and multiline fields are supported. Accepts LF/CRLF/CR and leading BOM. Invalid quoting stops the report. Compare width with the first record; headers are trimmed and compared case-sensitively. A value starting with =, +, - or @ after whitespace triggers a formula warning, including negative numbers. This conservative heuristic may miss application-specific behavior. It neither sanitizes data nor certifies safety or CSV compliance.