Duplicate Lines
TextEverything runs locally in your browser — nothing is uploaded
Four outputs for four questions: the deduplicated list, only the lines seen more than once, only the lines seen once, and each repeated line with its count. The rule is whole-line equality; text pasted from Windows programs uses `\r\n` line endings, so the tool strips the trailing `\r` first — otherwise the last line is wrongly judged unique. Whether blank lines count is a switch, on by default so nothing is dropped silently. Everything runs in your browser; nothing is uploaded and nothing goes over the network.
Features
- Four outputs: deduped list, repeats only, uniques only, repeats with counts
- Whole-line equality, with Windows \r handled correctly
- Ignore case and ignore leading/trailing whitespace, separately
- Sort optionally, or keep first (or last) appearance order
- Count blank lines or not — a switch, on by default
- “With counts” puts the count first so it pastes into a spreadsheet
- Reports the total, the unique count, and how many lines repeat
- Everything runs locally in your browser; nothing is uploaded
How to use
- Paste the lines you want to process
- Pick an output mode (dedupe / repeats / uniques / repeats with counts)
- Tick ignore case, ignore whitespace, sort, and the other options as needed
- The result updates as you type; click Copy to take it
FAQ
- Will text copied from Windows be counted wrongly?
- No. Programs such as Notepad and Excel use `\r\n` line endings. If you split on `\n` only and leave the trailing `\r`, the last line no longer equals an earlier identical one. This tool strips the trailing `\r` first, so the comparison is correct.
- Do blank lines count as duplicates?
- By default yes — it is safer not to drop input silently. If your text has many blank lines you do not want in the stats, untick “Count blank lines too”.
- Why does “with counts” put the count first?
- Writing `3 × line` means you can paste the result into a spreadsheet and sort by the first column to get a frequency table, with no column rearranging.
- When ignoring case, which spelling is kept?
- The first occurrence as written — it is never lowercased. Ignoring case only affects whether two lines count as the same, not what is kept.
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