Find Duplicate Lines
List every line that appears more than once, with a count next to it. Spot repeats in lists and logs fast. Free.
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List every line that appears more than once, with a count next to it. Spot repeats in lists and logs fast. Free.
How to use Find Duplicate Lines
- Paste or type your contentThe result appears as you type — there is no submit button.
- Read and copy the resultThe output updates live and the copy button takes it in one click.
Nothing you enter leaves your device
All of the work happens inside your browser. Whatever you type is never packaged up and sent to a server, and no request this page makes carries it.
That makes it safe for contract amounts, personal details and internal documents you would rather not hand to a third party — close the tab and it is gone.
What this tool does not do
Find Duplicate Lines only does what a browser can do on its own — it talks to no backend service. So it keeps no history for you and syncs nothing across devices; if you need a record, copy or download the result.
It is also not a substitute for professional judgement. For legal, medical or tax decisions, treat the output as a starting point rather than a final answer.
Frequently Asked Questions
- What does it show?
- Only lines that occur two or more times, each with how many times it appears, sorted by frequency.
- Does it compare exactly?
- Yes. Lines must match exactly, including case and spacing, to be counted as duplicates.