What This Tool Does
Paste a block of text and this tool splits it into individual sentences, identifies any that appear more than once, removes the repeats, and reassembles the remaining sentences into clean prose. It uses punctuation-aware splitting that recognises common abbreviations — such as Dr., Mr., vs., and etc. — so a period after an abbreviation does not incorrectly trigger a sentence break. The case-insensitive mode treats a sentence and its all-caps or title-cased duplicate as the same entry, which is useful when content has been merged from multiple sources with inconsistent formatting.
How to Use
- Paste your text into the Input panel.
- Choose Case-sensitive if exact character matching matters, or Case-insensitive to catch duplicates that differ only in capitalisation.
- Keep Trim whitespace enabled so sentences with different amounts of surrounding space still match correctly.
- Copy or download the deduplicated text from the Output panel.
Frequently Asked Questions
How does the tool decide where one sentence ends and another begins?
The tool splits on the characters ., !, and? when they are followed by whitespace or appear at the end of the text. To avoid false splits at abbreviations, it first protects known short forms — Dr., Mr., Mrs., Ms., Prof., vs., etc., Inc., Ltd., and several others — by temporarily replacing their periods before splitting, then restoring them afterward. This is not perfect for every edge case, but it handles the most common sources of incorrect splits in everyday text.
When would I need to remove duplicate sentences?
Duplicate sentences appear most often when documents are merged or assembled from multiple sources — for example, combining several drafts of an article, importing content from a CMS that re-inserted boilerplate paragraphs, or cleaning up a transcript where a speaker repeated themselves. AI-generated text sometimes repeats sentences across long outputs. This tool gives you a quick way to detect and remove that redundancy without reading through the entire document manually.
Does it preserve the order of sentences?
Yes. When a sentence appears multiple times, only the first occurrence is kept and all subsequent duplicates are removed. The remaining sentences stay in the same order they appeared in the original text. The output is then joined back into a single paragraph with single spaces between sentences. This means the flow and narrative structure of your text are preserved while the redundancy is eliminated.
Is my text sent to a server?
No. All processing happens in JavaScript running locally in your browser. Your text is never transmitted to any server, stored in a database, or logged anywhere. You can safely use this tool with confidential documents, internal reports, or sensitive drafts — there is no network request involved at any point.