How to use the remove duplicate lines
- Paste your list, one item per line. Duplicates are removed as you type.
- Decide whether Apple and apple should count as the same line (case sensitivity), whether spaces around lines should be ignored, and whether empty lines should go.
- Keep the first occurrence order or sort the unique lines A→Z or Z→A.
- Copy the cleaned list or download it as a text file.
Features
- Case-sensitive or case-insensitive matching
- Whitespace trimming so “ apple” and “apple” match
- Optional removal of blank lines
- Original order preserved (first occurrence wins) or natural sorting (item2 before item10)
- Counts of lines in, kept and removed
Typical uses
Cleaning email lists exported from several sources, de-duplicating keyword lists for ads or SEO, tidying a list of URLs, merging to-do lists, or removing repeated log lines before sharing them. Because the first occurrence is kept, the result stays in the order you assembled the list.
How matching works
With trimming on, each line is compared after removing leading and trailing spaces and tabs; the kept line is the trimmed version. Case-insensitive matching uses locale-aware lowercasing, so İ and i are handled correctly in Turkish text. Sorting is natural, meaning numbers inside lines sort by value rather than character by character.