Remove Duplicate Lines
Clean repeated lines from any text block in seconds with deterministic output and flexible options.
Output
What this tool does
This tool removes duplicate lines from newline-separated text. It is designed for practical tasks like cleaning exported reports, normalizing logs, deduplicating keyword lists, and preparing text data before import into another system. Instead of manually scanning for repeated rows, you can paste your data, choose processing options, and get a clean output immediately.
The utility is deterministic. That means when your input and options are the same, your output will always be the same. This makes the tool reliable for repeat workflows where consistency matters. It also supports common processing preferences such as case-insensitive comparison, whitespace trimming, optional blank line removal, and optional sorting.
How to use it
- Paste your text where each item is on a new line.
- Select behavior options (case sensitivity, trim, remove blank lines, sort).
- Click Run Tool.
- Copy the cleaned output and use it in your next workflow step.
Popular use cases
- SEO and content ops: remove repeated keyword lines collected from multiple sources.
- Engineering and DevOps: clean repeated log entries before analysis.
- Sales and operations: deduplicate contact IDs or task labels exported as text.
- Data preparation: normalize line-based datasets before import.
- Prompt and config cleanup: clean repeated instruction lines.
Why this approach works
The tool performs an efficient single-pass dedupe using a set lookup for seen values. This gives predictable performance for medium-to-large line lists while preserving first-occurrence order unless sorting is explicitly enabled. In short: fast processing, understandable output, and fewer mistakes than manual cleanup.
FAQ
Will this change my original line order?
Order is preserved by default. If you enable sorting, output is alphabetically sorted.
Can I make it case-insensitive?
Yes, uncheck case sensitivity to treat upper/lower case variants as duplicates.
Does trimming happen before dedupe?
Yes, when enabled, leading/trailing spaces are removed before duplicate comparison.
Related tools
- Case-insensitive duplicate remover guide
- Remove blank + duplicate lines
- Sort and deduplicate lines
- Case converter (coming soon)
- All tools
Privacy assurance: This tool is designed to process your request quickly with operational safeguards. We do not sell user input data.
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