Free online remove duplicate lines tool
This tool takes any list of lines and returns only the unique ones, deleting every repeated line for you. It's perfect for cleaning up email lists, keyword lists, log files, CSV columns, and any text where the same line appears more than once. The first time each line shows up is kept, and the result updates live as you type or paste — nothing ever leaves your browser.
How to remove duplicate lines
- Paste or type your lines into the Input lines box.
- Watch the Unique lines box fill in with the duplicates removed.
- Optionally tick Ignore case or Trim whitespace for comparison to catch near-identical lines.
- Tick Remove empty lines or Sort result alphabetically to tidy the output further.
- Check the input/output counts and separate duplicate/empty-line totals, then copy or download the clean list. Use Load example to try it or Clear to start again.
Handy options for cleaner lists
Ignore case treats Hello and hello
as the same line, while still keeping the exact text of the first one.
Trim whitespace for comparison ignores stray spaces and tabs at the start
or end of a line when comparing, so accidental indentation won't hide a
duplicate. Combine them with sorting to turn a messy paste into an ordered,
duplicate-free list in one step. The first occurrence retains its original
casing and whitespace even when comparison options are enabled.
Related text tools
Need natural or numeric ordering? Try Sort Text Lines. Need to flatten text into a single block instead? Try the Remove Line Breaks tool. To measure the length of your cleaned-up text, head over to the Word Counter. Everything runs privately in your browser, with no sign-up and no limits.