You downloaded a CSV file and want to inspect or tidy it without uploading it to a website first.
This file-first formatter opens the file locally in your browser, parses it, and lets you view aligned columns or export cleaned CSV.
How to use CSV File Formatter
- Open a .csv file with the file button, or paste its contents.
- Choose Aligned monospace text or Cleaned CSV as the output.
- Copy the result or download the formatted file.
What you can do with it
- Inspect a downloaded CSV export locally.
- Clean a file and re-download it for import.
- Check columns in a CSV without a spreadsheet.
Good to know
The browser reads your local file with the FileReader API, so large files are processed on your device and nothing is uploaded. You can also drag a CSV file onto the input.
Frequently asked questions
Is the file uploaded anywhere?
No. It is read locally with the FileReader API and stays on your device.
Can I open large files?
Yes, within your browser memory. Very large files may take a moment, and a notice appears for big inputs.
Which output should I download?
Download cleaned CSV for importing elsewhere; the aligned view is for reading only.