Add 1-based line numbers or remove matching numeric prefixes.
Type or paste on the left — the result updates as you type.
Remove mode recognizes only a leading number followed by a period and a space. Blank lines are numbered too.
Up to 100,000 UTF-16 units per input and 1,000,000 per result. See the supported formats and examples below.
Tool page updated: 2026-09-27
