🔄 Dedup Lines
Free online duplicate line remover. Drop in any text and instantly strip out repeated lines. Choose between keep order (first occurrence wins) and sort & unique (alphabetical). Live line count shows how many lines you removed. Perfect for data cleaning, list dedup, log preprocessing, and CSV cleanup. Everything runs locally — no data leaves your browser.
⚙️ Deduplicate Text
Enter text, choose a mode, and remove duplicate lines.
❓ Frequently Asked Questions
Keep order (the default) walks the text top-to-bottom and keeps the first occurrence of each line while discarding later duplicates — relative order is preserved. Sort & unique first sorts all lines alphabetically, then removes duplicates — great when you want a tidy, alphabetized list of every unique value.
Yes, by default. "Apple" and "apple" are treated as different lines. If you need case-insensitive dedup, run the input through the Case Converter first to normalize all lines to the same case.
The dedup runs entirely in your browser using an in-memory hash table, so it stays snappy up to tens of thousands of lines. For very large inputs (hundreds of thousands of lines) memory may become the bottleneck. Nothing is sent to a server, so your data never leaves your machine.