Sed One-Liner Generator
Choose a bounded sed task, fill in its parameters, and compare the input with a browser-local preview.
Sed one-liner generator
A QUICK WALKTHROUGH
How to use this tool
- Choose a search, line, whitespace, prefix, or numbering task.
- Enter the parameters and sample text.
- Review the generated command and local before/after preview; copy the command only when you are ready to use it yourself.
Common sed operations
The generator covers search and replace, deleting or extracting line ranges, deleting or extracting matching lines, trimming whitespace, adding prefixes or suffixes, and numbering lines.
Preview and command are separate
The preview uses the browser JavaScript regular-expression engine for predictable local feedback. The generated command is a shell snippet for you to inspect and run in your own environment; this tool never executes it or accesses files.
Local limits
Sample text is limited to 50,000 characters. No text, pattern, filename, or generated command is uploaded.
GOOD TO KNOW
Common questions
Does this run sed on my files?
No. It only displays a command and previews the transformation of text pasted into the page.
Is the preview exactly the same as every sed implementation?
No. The preview uses JavaScript regular expressions, while sed dialects differ. Treat the command as a starting point and verify it in your target shell.
Can I use arbitrary shell syntax?
No. This bounded tool generates fixed sed snippets from text parameters and does not execute shell input.