Line Numberer

Sometimes you need numbers down the left side of a block of text, and sometimes you need them gone. This tool does both. You pick where counting starts, what sits between the number and the text (a dot, a bracket, a colon, a tab), and whether blank lines get skipped. Zero padding keeps everything lined up once the list passes nine or ninety-nine lines.

How to use it

Paste the text, one entry per line.
Choose between adding and removing numbers.
Set the starting number and the separator that suits your document.
Copy the result back out.

When it helps

Numbering lines of a log or code snippet so people can refer to "line 14" in a review.
Turning a plain list into a numbered one for a document or chat message.
Stripping numbers from a list you copied off a web page so you can re-sort or reuse it.
Preparing numbered references for a script or transcript.

Good to know

Padding with zeros makes 7 and 12 display as 07 and 12, which keeps columns straight in monospaced text.
When removing numbers, formats like "1.", "2)" and "3:" are all recognised, so mixed lists clean up in one go.
Leave the skip-empty-lines option on if your text has paragraph gaps, otherwise the blank lines get numbers too.

Why line numbers help

Numbered lines turn a vague "somewhere around the middle" into a precise "line 14". That is why code reviews, log excerpts, legal drafts and transcripts are so often numbered. When two people discuss the same block of text, a number on every line removes the ambiguity, and it makes it easy to refer back to a spot later.

The reverse job is just as common. Text copied from a website or a PDF often arrives with numbers attached, and those numbers get in the way if you want to reuse the text. Removing them by hand is slow, which is where the remove option comes in. It recognises numbers followed by a full stop, a bracket, a colon, a dash or a tab.

Worked example: numbering a short script

Take three lines: "Open the file", "Edit the header", "Save and close". With the start set to 1 and the separator set to a full stop, the result reads 1. Open the file, 2. Edit the header, 3. Save and close. Change the start to 10 and you get 10, 11 and 12, which is useful when you are continuing a list that began elsewhere.

With zero padding on and a list of 120 lines, the first nine numbers become 001 through 009. That keeps the left edge straight in monospaced text, so the text itself starts at the same column on every line. If you have blank lines for spacing and leave skipping on, those blank lines stay blank and the numbering continues in sequence without gaps.

Things to watch for

Numbering counts lines, not paragraphs. If your text wraps in the original and you paste it with its wrapped lines, each wrapped line will be numbered separately. Run it through the Line Break Remover first if you want one number per paragraph.

Tabs as separators suit pasting into a spreadsheet, where the number lands in one cell and the text in the next. For readable plain text, a full stop or bracket looks better. Whichever you choose, you can strip the numbers again later with the remove option.