Controlled deduplication
Choose whether case, accents, surrounding spaces, and repeated whitespace matter.
Input list0 B
Result0 B
Add at least one list item.
0items0non-empty0unique0duplicates0characters
Frequency0
| Value | Count |
|---|
List basics
Understanding lists
A list is an ordered collection of items. In plain text, items are usually separated by line breaks, commas, tabs, or another delimiter.
Duplicate rules depend on normalization. “Apple” and “ apple ” can be treated as different or equal depending on case and whitespace settings.
What it does
What this tool does
Clean a list while keeping the first original spelling and order for every retained item.
Useful views
Inspect all, unique, or repeated values before exporting.
Filter and replace
Use plain text or a regular expression, then replace matches when needed.
Frequency evidence
See how often normalized values occur.
How to use
How to use it
Add the list
Paste text, open a local file, or load the sample.
Set boundaries
Confirm the input and output separators.
Define equality
Choose normalization and filtering options.
Apply and export
Review counts, then copy, download, or reuse the result.
Limits
Common errors and limits
Normalization changes identity
Ignoring accents may merge “cafe” and “café”. Review the frequency table before deleting duplicates.
Regular expressions can be broad
Test a pattern on a small sample before replacing text.
FAQ
Frequently asked questions
Does it preserve order?
Yes. Deduplication keeps the first occurrence and its original spelling.
Does my list leave the browser?
No. Processing and file reading happen in this tab.
Can I keep only duplicates?
Yes. The duplicate view returns each repeated normalized value once.
What separators are supported?
New lines, blank lines, commas, semicolons, tabs, pipes, spaces, and a custom separator.