Filter Text Lines

Filter Text Lines

The tool splits the input on normalized line endings and keeps lines that contain a search value. Literal matching is the default; Use regular expression, Case sensitive and Exclude matching lines are all off initially.

Literal matching compares a lowercased copy of each line and query unless Case sensitive is selected. It searches for a substring rather than requiring an exact whole-line match.

Exclude matching lines reverses the selection, keeping only lines that do not match. For lines apple, banana and apricot with query 'ap', the default output is apple and apricot; Exclude returns banana.

Regular-expression mode passes the entered pattern directly to JavaScript RegExp with an optional case-insensitive flag. An empty query is rejected and an invalid pattern is shown as an error; users should treat characters such as brackets and plus signs as regex syntax in that mode.

Filtering runs locally in the browser and retains each selected line's original text and order. It does not edit matching text within a line, sort results or provide a file upload workflow.