Use the free Add Line Numbers to Text below: your data never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
Why number the lines of a text
Numbered lines are easier to talk about. In a meeting you can say “look at line 14” instead of reading out a whole sentence and hoping everyone finds it. In a review you can point a colleague at an exact line. In a classroom a teacher can ask students to read lines 20 to 30. Programmers live by line numbers because error messages and debuggers report them, and editors and lawyers number lines for the same reason: a number removes all ambiguity about which line you mean.
Numbering by hand is slow and fragile. Insert one line near the top and every number below it is wrong, so you renumber the whole list. Paste a list from somewhere else and you start counting from scratch. A tool that numbers lines automatically removes that chore entirely, and it renumbers perfectly every time you change the text and run it again.
How this tool works
Paste your text into the box. The tool splits it into lines and puts a number in front of each one. You choose the format: a number followed by a dot, a closing parenthesis, a colon, square brackets, or just the number and a space. You also choose the starting number, so a second chunk of a longer document can continue from 51 instead of restarting at 1, and you can switch on zero padding, which lines the numbers up neatly when a list runs past 9 or 99.
Empty lines are a choice, not an accident. By default they are skipped, so a blank line between paragraphs does not consume a number and does not get one printed. If you uncheck that option, every line gets a number, including blank ones, which matches the way code editors number lines. The result keeps your original text untouched apart from the added numbers, and you can copy it straight into a document, an email or a chat message.
When to use it
Use it before sharing a draft for feedback, so reviewers can refer to lines by number. Use it when preparing a script, a poem, a speech or a set of instructions that people will discuss line by line. Teachers use numbered texts for reading exercises and tests. Support teams number pasted logs and transcripts so a customer can point at the exact line where an error appears. Writers number scenes and verses while restructuring a piece.
It is also handy for checklists and inventories. Number a list of items before a stock count or a packing session, and two people can divide the work by number ranges without confusion. Numbered lines also make it easy to spot a missing item: a gap in the sequence stands out immediately.
What numbering does not do
Numbering adds labels; it does not change the meaning of your text, and the numbers are plain text, not a live feature. If you edit the numbered result in another program, the numbers will not update themselves, so always edit the original and renumber. Also note that very long lines are not wrapped or split by this tool: a line is whatever sits between two line breaks, however long it is. If your text came from a word processor with wrapped paragraphs, each paragraph is one line here.
Be careful with starting numbers and padding when combining chunks. If two chunks both start at 1, their numbers will collide when pasted together. Number the whole combined text in one pass whenever you can, or set the starting number of each later chunk to continue the sequence.
Tips for tidy numbered text
For lists longer than 99 lines, turn on zero padding so the numbers align in a straight column, which is much easier to scan. For short lists, plain “1.” numbering reads most naturally. If you plan to sort or process the lines later, a format like “001.” sorts correctly as text, while unpadded numbers do not. And as always, the tool runs entirely in your browser: nothing you paste leaves your device.