Clean and Normalise CSV Files
Fix CSV exports that won't import cleanly. Re-delimit the file, trim stray spaces, drop blank lines, pad short rows to a consistent column count, choose quoting and line endings, and preview the result as an aligned text table.
How to format a CSV file
- Paste CSV text or upload a .csv, .tsv or .txt file of up to 50 MB.
- Leave the input delimiter on auto-detect (or set it), and pick the output delimiter, quoting style and line endings.
- Choose the clean-up options: trim spaces, remove empty rows and pad short rows.
- Check the counts and the aligned table preview, then copy or download the cleaned file.
Supported formats
- Input
- CSV, TSV, TXT
- Output
- CSV, TSV
- Maximum size
- 50 MB per file (limited by your device's memory)
Ragged rows and why imports fail
Many databases and import wizards reject a CSV when one row has fewer fields than the header — often because trailing empty cells were dropped by the exporting program. Padding fills those rows with empty values so every row has the same column count. Rows with extra fields are counted but left intact, since removing data automatically would be risky. When the file is clean, the CSV to JSON Converter can turn it into structured data.
Benefits
- Parses quoted fields properly, so commas and line breaks inside cells survive the re-delimiting.
- Reports exactly how many rows were removed or padded so you know what changed.
- Aligned text-table preview makes misplaced columns obvious at a glance and can be copied into READMEs or tickets.
Limitations
- Trimming removes leading and trailing spaces from every cell, including any that were intentional.
- Rows with more fields than the widest row expected are not split or merged automatically.
- Character encoding is not converted; files are read as UTF-8, so legacy ANSI/Latin-1 files may show garbled accents.
Privacy and security
Pasted CSV is processed by JavaScript in this tab and uploaded files in a Web Worker on your device. The data is never uploaded or stored.
Read our privacy policy for details about the site as a whole.
Frequently asked questions
When should I quote every field?
Minimal quoting (only where a value contains the delimiter, a quote, a line break or edge spaces) is standard and smallest. Some older importers expect every field quoted — choose that only if your target requires it.
How do I convert a semicolon CSV from Excel to comma-separated?
Paste or upload the file, leave the input delimiter on auto-detect (or choose Semicolon), and set the output delimiter to Comma. Quoted values containing commas are handled automatically.
Can I create a TSV file?
Yes. Set the output delimiter to Tab and the download is saved with a .tsv extension.