Add numbers to your text lines with a custom start, increment and separator. Skip blank lines or pad numbers with zeros, then copy or download the result locally.
Your lines are numbered on your device with no uploads, account, dependencies or browser storage. The original remains available for comparison, and line order and content stay in place while number prefixes are added.
By default, every physical line receives a prefix, including blank lines. Visual wrapping in the editor does not create a new line. An ending newline terminates the last entry and does not create an extra empty entry. Empty input has zero lines.
Whitespace-only lines are left exactly where they are, with their whitespace intact. They do not receive a prefix or consume a number. JavaScript Unicode whitespace rules identify blank lines; zero-width joiners and other non-whitespace marks do not count as blank.
Start can be a whole number from 0 to 1,000,000,000. Increment must be a whole number from 1 to 1,000,000. The sequence advances only for numbered lines. Zero padding matches the width of the final number, so a sequence ending at 12 starts with 01 when enabled.
No. A new prefix is added before the original line, including any indentation or existing numbers. This tool does not detect or replace numbering. Review the result before using it as code, structured data or a formatted document.
CRLF and CR endings normalize to LF, matching the browser editor. An ending newline is retained if present. Skipping blank lines does not remove them; use Whitespace Cleaner if you want blank-line cleanup.
The input limit is 200,000 UTF-16 text units and 20,000 line entries. Some emoji use multiple units. Oversized input remains unchanged while processing is unavailable. Clear removes the input and output but keeps your selected options.
