Row count, column count, empty cells, duplicates, inferred column types, and a live data preview — without opening a spreadsheet app. 100% local. No uploads.
[.csv]
Drop CSV or TSV files here or click to browse
CSV · TSV · TXT · up to 25 MB per file · up to 20 files
Files: 0Total rows: 0Issues found: 0Skipped: 0
Known Limitations
Delimiter is auto-detected (comma, tab, semicolon, pipe) by sampling the first 10 lines — unusual delimiters may need manual adjustment in the source file
Files are decoded as UTF-8; files saved in Windows-1252 or Latin-1 encoding may show garbled characters in non-ASCII fields
Duplicate row detection compares the full serialised row string — rows that are logically identical but differ in whitespace or casing are not flagged
Column type inference samples every value in each column — integer, float, boolean, ISO date, or text. Mixed columns are flagged as mixed
Very large files (>25 MB) and files over 250,000 parsed rows are rejected to protect browser stability; the data preview is capped at 20 rows
Quoted fields containing newlines (RFC 4180 multiline cells) are parsed correctly; malformed unterminated quotes are rejected clearly
Duplicate staged files are skipped by matching file name and size