Remove Duplicate / Empty Lines
Clean up lists, logs, and CSV-like text in one click — this text cleaner deduplicates lines, removes blank lines, sorts A→Z or Z→A, and trims whitespace. See before/after line counts and control how whitespace and case are handled, entirely in your browser.
How To Use
- Paste your text with one item per line.
- Choose an action: Remove duplicates, Remove empty lines, Trim whitespace, or Sort A→Z / Sort Z→A.
- Tick the options for case- and whitespace-sensitive comparisons.
- Read the output and its line-count summary.
Usage Example
Input:
apple banana apple cherry
After Remove duplicate lines and Remove empty lines:
apple banana cherry
Output line count drops from 5 to 3.
Use Cases
This text cleaner is a quick win whenever a pasted list is full of redundancy. Normalize a mailing list or spreadsheet column by removing duplicated emails and blank rows before an import. Clean up server logs or configuration files cluttered with repeated lines. Prepare keyword lists, tag clouds, or CSVs for analysis by deduplicating and trimming every row. When the "ignore case" option is on, near-identical lines such as "Apple" and "apple" collapse into one, which is useful for comparing names or labels produced by different people.
Best Practices
- Usually combine Remove empty lines and Trim whitespace before deduplicating, so whitespace-only or padded duplicates are caught.
- Deduplication keeps the original order; lines are only re-sorted when you click Sort A→Z or Sort Z→A — useful for unordered lists like tags or keyword exports.
- Turn on ignore case only when you genuinely want "Foo" and "foo" considered the same value.
- Check the line-count summary before and after to confirm how much was removed.
Frequently Asked Questions
Is the order preserved?
Yes for deduplication: the first occurrence of each duplicate is kept, so the original order is maintained. Lines are only reordered when you explicitly click Sort A→Z or Sort Z→A.
What does "ignore case" do?
When enabled, lines like Apple and apple are treated as duplicates and only the first is kept.
Is my text uploaded?
No. All cleaning happens locally in your browser with native string operations. Nothing is sent to a server.
Can I reuse this to build lists and tags?
Yes. Paste a messy list of tags, emails, or IDs, remove duplicates and empty lines, then export the clean result — a quick way to normalize data for imports.
What does "Trim whitespace" do?
It strips leading and trailing spaces from every line — used for comparisons and also applied to the output. This is often combined with deduplication so that " apple " and "apple" are recognized as the same line.
Does the tool sort lines?
Yes. Sort A→Z and Sort Z→A order lines alphabetically using your locale's collation. With "Trim whitespace" on, lines are trimmed before sorting and the trimmed lines are output; with "ignore case" on, the comparison is case-insensitive, so "Apple" and "apple" count as equal and keep their original input order relative to each other.