Remove Duplicate Lines
Remove duplicate lines from lists, logs, emails, or any multiline text online. Keep the first occurrence, choose case-sensitive matching, and copy the unique lines instantly.
About Remove Duplicate Lines
Paste any list or block of text and instantly remove duplicate lines, keeping only the first occurrence of each unique line and preserving the original order. It is ideal for cleaning email and subscriber lists, deduplicating CSV exports, trimming repeated log entries, and tidying keyword lists for SEO. Choose case-sensitive matching when capitalization matters, or ignore case to treat 'Hello' and 'hello' as the same. Everything runs in your browser - your data is never uploaded.
How to Use Remove Duplicate Lines
- Paste your text with one item or entry per line.
- Choose case-sensitive or case-insensitive matching.
- The tool removes repeated lines, keeping the first occurrence of each.
- Optionally review how many duplicates were removed.
- Click Copy to grab the deduplicated list.
Remove Duplicate Lines Examples
Email list
Remove duplicate email addresses from an exported subscriber list.
Keyword list
Deduplicate a large SEO keyword export so each term appears only once.
Log file
Collapse repeated log lines to quickly see the unique events that occurred.
Read the full guide
How to Use Remove Duplicate Lines: Complete Guide (2026) - 5 min read
Frequently Asked Questions about Remove Duplicate Lines
- How do I remove duplicate lines?
- Paste your text with one entry per line and the tool keeps the first occurrence of each unique line while removing every later repeat. The original order is preserved, and you can copy the cleaned result in one click.
- Does it keep the original order?
- Yes. The first time a line appears it is kept in place; only its later duplicates are removed. This preserves the order of your list rather than sorting it alphabetically.
- Does it work case-insensitively?
- Yes - toggle case-sensitive matching off to treat "Hello" and "hello" as duplicates. With case sensitivity on, they are treated as different lines.
- Are blank lines removed too?
- Empty lines are treated as lines, so repeated blank lines can be deduplicated as well. The first occurrence of each unique line - including a single blank line - is always kept.
- Does it also remove duplicate words within a line?
- No - this tool works on whole lines, comparing each full line against the others. To clean spacing within lines, use the Remove Extra Spaces tool alongside it.
- What is remove duplicate lines used for?
- Common uses include cleaning email lists, deduplicating CSV exports, removing repeated log entries, merging lists, and tidying keyword lists for SEO.