CSV row-width checker

Early public prototype · Unvalidated hypothesis · v0

Check comma-delimited UTF-8 CSV locally. The first logical record is the header. No upload, storage, or display of filenames or cell values.

Choose exactly one CSV file (maximum 5,000,000 bytes), or drop it here.

Ready. Choose a file or try the sample.

Limitations

Comma delimiter only; no repair, delimiter inference, schema or type validation. Matching widths do not establish import validity. Record numbers are logical records, not physical lines. Quoted multiline fields are supported. Only the first 200 mismatches are listed. Invalid UTF-8 and malformed CSV produce diagnostics instead of partial reports.

Sample use is not user validation. User-file start and completion emit only local browser events with a constant source label; no file contents are transmitted. Optional pilot measurement above sends only anonymous workflow events after consent. No demand, repeat-use, performance, or independent acceptance claims are made.