Primary example
Before
apple banana apple Banana cherry
After
apple banana Banana cherry
Remove Duplicate Lines
Deduplicate repeated lines in logs, email lists, or SKU exports with optional case sensitivity and blank-line handling.
Remove Duplicate Lines
Build a clean unique list with optional frequency counts and duplicate tracking.
0
Original lines
0
Unique lines
0
Duplicates removed
0%
Reduction %
—
Most repeated item
0%
Unique ratio
Paste or type one item per line to deduplicate.
One item per line
Unique lines or frequency counts
Lines dropped during deduplication
Your text stays in your browser — nothing is uploaded.
How to Use
- Paste one item per line—emails, URLs, tags, or log entries.
- Toggle case sensitivity if "Apple" and "apple" should count as duplicates.
- Choose whether empty lines participate in deduplication.
- Copy the unique list from the output panel.
Example
List with repeats
apple banana apple Banana cherry
Unique lines kept
apple banana Banana cherry
Before and After Examples
What This Tool Does
Remove Duplicate Lines scans your text top to bottom, keeping the first occurrence of each line and dropping later matches. Unlike sorting alone, it preserves the original order of unique entries, which matters for timelines and prioritized lists where sequence carries meaning.
Guidelines
Tip
Cleaning mailing lists exported from multiple spreadsheets
Practice
Deduplicating server log paths before analysis
Use case
Removing repeated hashtags or SKU codes
Note
Preparing unique keyword lists for research
Common Uses
Best Practices
Paste one item per line—emails, URLs, tags, or …
Toggle case sensitivity if "Apple" and "apple" …
Choose whether empty lines participate in dedup…
Copy the unique list from the output panel.
Cleaning mailing lists exported from multiple s…
Deduplicating server log paths before analysis
Removing repeated hashtags or SKU codes
Preparing unique keyword lists for research
Popular Workflows
Notes & Limitations
All processing runs locally in your browser. Results may vary with edge-case characters or very large inputs.
Frequently Asked Questions
Which duplicate is kept?
The first appearance stays; later identical lines are removed.
Does trimming affect matching?
Leading or trailing spaces can make lines look unique; trim first with Trim Text if needed.
Can duplicates differ only by case?
Disable case sensitivity to treat "Test" and "test" as the same line.
Will partial line matches dedupe?
Only entire lines match; use Find and Replace for substring duplicates.