Fixed-Width Text Parser to CSV / JSON
Convert
Many legacy systems, mainframe reports and COBOL exports store data in fixed-width columns instead of using a delimiter. Paste that text, list the column widths (e.g. 6 3 8), and each line is sliced into fields and exported as CSV or JSON. Optionally trim padding spaces, and treat the first row as a header to build JSON objects keyed by column name. Everything runs locally in your browser — nothing is uploaded.
How to use
- Paste your fixed-width text, one record per line.
- Enter the column widths separated by spaces or commas (e.g. 6 3 8).
- Choose CSV or JSON output and toggle trimming.
- For JSON, enable 'first row is header' to key objects by column name, then copy the result.
Frequently asked questions
- How do I know the column widths?
- Count the characters each column occupies in the source layout, including padding spaces. Most fixed-width specs document the widths; you can also align the text in a monospace editor and count.
- What happens if a line is shorter than expected?
- Fields past the end of a line come out empty. Lines longer than the total width have the extra characters ignored.
- How is the CSV quoted?
- Fields containing a comma, double quote or line break are wrapped in double quotes, and inner quotes are doubled, following RFC 4180.
- Is my data uploaded?
- No. Parsing happens entirely in your browser; nothing leaves your device.
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