Text tool
Line Numberer
Add incrementing line numbers with a custom starting value and separator, or remove existing numbers and separators from pasted text.
Output
How numbering and removal work
The starting number field controls where numbering begins; the default is 1. The separator dropdown determines what appears between each number and its line text: Period adds ". ", Parenthesis adds ") ", Dash adds " - ", and Tab inserts a single tab character. When Add mode is active, each line receives an incrementing integer followed by the chosen separator and the original text. The output area displays the numbered result.
The Remove matching line numbers checkbox reverses the process. When enabled, the tool looks for a leading integer followed by your selected separator at the start of each line and strips it away, leaving only the text after the separator. Removal only works if the line begins with the exact pattern (a number, then the separator, then content), so if you numbered with '. ' but the line now starts with a different separator or different text, removal will not affect that line.
Adding and removing line numbers
- Input lines: "Alpha", "Beta", "Gamma"
- With starting number 1 and Period separator: "1. Alpha", "2. Beta", "3. Gamma"
- With starting number 5 and Dash separator: "5 - Alpha", "6 - Beta", "7 - Gamma"
- Removing from "1. Alpha", "2. Beta" (with Period separator selected): returns "Alpha", "Beta"
- Removal requires matching separator; removing with Dash selected from "1. Alpha" leaves the line unchanged because '. ' does not match ' - '
Preparing code samples and procedure documentation
A common use case is adding numbers to a code listing. If you paste ten lines of code from a text editor without line numbers, run the numberer with starting number 1 and Period separator to produce a numbered reference list you can discuss or troubleshoot. Someone can then say 'line 5 has the bug' instead of 'the line with the loop has the bug.' Starting number can be adjusted if your sample begins at line 50 in the full file.
For procedure documentation, numbering the steps makes them referenceable. A list of eleven installation steps becomes "1. Download the installer", "2. Run the executable", and so on. If you later need to remove the numbers to extract just the procedure text for another format, the Remove matching line numbers checkbox does this instantly, provided the separator matches what you used for numbering.
Common numbering scenarios
- Documenting a conversation: paste chat messages and number them with starting value 1 and Dash separator to create a timestamped, numbered transcript that is easy to reference.
- Outlining sections of a document: number each section heading with starting value 1 and Period separator. An A–Z sort later keeps them in order, since the comparison reads the leading digits as numbers.
- Reconciling a list: paste two columns of data, number each with starting value 1 and Tab separator, import into a spreadsheet, and match rows by number.
- Stripping old numbering before re-numbering: paste lines like "1. Item" with the matching separator selected, enable Remove to get "Item", then disable Remove and number again from a new starting value.
- Creating a voting or scoring list: number items and ask others to assign scores to each numbered item, making it unambiguous which item received which score.
Frequently asked questions
Can I start numbering from zero?
Yes. The starting number field accepts any integer, including 0. Enter 0 to produce "0. Alpha", "1. Beta", etc.
What is the Tab separator used for?
Tab separators are useful when exporting to spreadsheet software. A number followed by a tab may be recognized as a separate column in some importers, keeping the number distinct from the line text.
If I change the separator, will removal still work on old numbering?
No. Removal looks for the exact separator you currently have selected. If your lines were numbered with '. ' but you select Dash, the removal will find nothing to strip because ' - ' does not match '. '.
Does removal affect lines that do not start with a number?
No. Only lines that begin with one or more digits followed by the selected separator are affected. Lines without that pattern are left unchanged.
Can I start numbering in the middle of a large document?
Yes, but you would need to split the text. Paste the portion you want to number separately, number it with your desired starting value, then manually reinsert it into the full document.
What happens if a line is blank?
A blank line still receives a number when adding numbers. "1. Alpha", "2. ", "3. Beta" shows the blank line with its number and separator, then nothing else.