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Line Counter

Count total lines, non-empty lines, and unique lines in any block of text. Add line numbers (with custom starting number and padding), filter lines that match or don't match a keyword or regex, and sort lines alphabetically or by length. Useful for processing logs, CSV data, code, and lists.

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Line Counter: questions

Can I filter with a regex?
Yes — enable "Regex" mode and type a valid JavaScript regular expression. Lines matching the pattern are kept (or removed, in "exclude" mode). Flags like /i for case-insensitive can be toggled.
Does it handle Windows (CRLF) line endings?
Yes — both \n and \r\n line endings are normalized before processing.
What is the line limit?
There is no hard limit — the tool processes as many lines as your browser can handle. Performance degrades gracefully above ~100 000 lines.
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