Put line numbers on a text — or take them off

The job

Two opposite chores share one tool. Adding numbers helps when someone will refer to "line 12" in a review or when a list must read as ordered. Removing them matters when you copy output that already has numbers — like `nl` output or a pasted code listing — and want the plain text back.

How to do it

Pick "add" or "remove" at the top, paste the text, and apply. When adding, choose the separator style (`1.` / `1:` / `1)` / space / tab), the starting number, whether to zero-pad, and whether blank lines get a number too.

• Zero padding keeps columns aligned: 01, 02 … 10 instead of 1, 2 … 10.
• Skipping blank lines keeps numbering on content lines only.
• Start at something other than 1 to continue a list across two pastes.

Worked example

A requirements list of 15 items pasted as `01. …`, `02. …` reads cleanly in a ticket and survives clients that strip Markdown list markup. Going the other way, `nl`-style output ` 7 some text` loses its numbers and returns the raw lines.

Limits

Removal is conservative: it strips a number ending in . : ) or a tab, or one indented like `nl` output — so "2024 report" and lines holding just a bare number are left alone. Adding never rewrites existing numbers; if the text is already numbered, remove first and re-add.