CSV Validator
Drop any .csv file to instantly check its structure. Auto-detects delimiter (comma, semicolon, tab, pipe), validates column consistency across every row, checks quoting, flags encoding issues, and previews the first few rows. Nothing leaves your browser.
CSV File
Drop a .csv file here, or
Supports .csv and .tsv files up to 50 MB
⛔
Wrong file type — only .csv or .tsv files are supported. You dropped a file.
Validation Errors
Warnings
✓ Valid CSV
Column Headers
Data Preview (first 5 rows)
How It Works
1
Drop your CSV fileDrag it onto the drop zone or click "browse" to select it from your device. Supports .csv and .tsv files.
2
Structure analysisThe validator auto-detects the delimiter, scans every row for column count consistency, checks quoting and escape characters, and detects encoding issues like a BOM marker or null bytes.
3
Review the reportGet a pass/fail result plus full stats: row count, column count, detected delimiter, empty cells, duplicate headers, and a live data preview.
What Gets Validated
- Delimiter detection — automatically identifies the delimiter by scoring candidates: comma
,, semicolon;, tab\t, and pipe|. - Column consistency — every data row is compared against the header column count. Rows with too many or too few fields are flagged with their line number.
- Quote integrity — detects unclosed double-quote fields that would cause parsers to misread the rest of the file.
- Duplicate headers — checks the first row for repeated column names, which break most data pipelines.
- Empty rows — counts and flags completely blank rows, which can cause off-by-one errors in downstream processing.
- Encoding issues — detects a UTF-8 BOM (byte order mark) and null bytes that indicate binary content or wrong encoding.
- File statistics — reports total rows, column count, empty cells, file size, line ending style (CRLF vs LF), and whether a header row was found.
- Data preview — renders the first 5 data rows in a formatted table so you can visually confirm the parse is correct.
🔒 Privacy & Security
All validation is performed locally using the Web File API and the FileReader API. Your CSV data is never sent to a server. Suitable for sensitive business data, customer records, or any private tabular content.