Remove Duplicate Words

Remove Duplicate Words takes any block of text and deletes the repeats, keeping the first copy of each word right where you first typed it. Paste a sentence, a keyword list, a comma-separated tag field, a whole messy paragraph, and every word that already showed up earlier gets dropped. The counts under the box tell you how many words you started with, how many got removed, and how many unique ones are left.

What actually sets this one apart from most free dedupers is what it refuses to touch. It changes nothing except the repeats. It will not sort your words alphabetically, it will not lowercase the copies it keeps, and the comma stays put on cat,. A lot of the free ones do at least one of those, so you paste your list back and find it re-ordered or flattened to lowercase, and now you are cleaning up the cleanup. Here the survivors come out exactly as you wrote them, same casing and same spot, with the repeats gone.

The matching is deliberately loose so it catches real duplicates, and the output stays faithful so it never touches your text. By default Apple and apple are treated as the same word, because real repetition almost never matches perfectly on case. Turn on Ignore punctuation and cat and cat, match too. But that loose matching only decides what counts as a repeat. Whatever word wins is the untouched original, first casing and first punctuation intact. Everything happens in your browser, so the text never leaves your device, nothing is uploaded, nothing is stored.

1. Paste your text into the top box. One word per line, a flowing paragraph, or a comma list, all fine.
2. Pick the separator. Spaces is the default and also splits on tabs and line breaks. Switch to Commas for a list like red, green, blue, where each comma-delimited item is one unit.
3. Set the two options. Case-insensitive is on by default, so The and the count as one. Flip on Ignore punctuation to make word and word, match.
4. Watch the counts. Original, removed, and unique update live as you type, so a high removed-count on a short paragraph tells you something before you even read the output.
5. Copy the result, or hit Clear to empty both boxes.

When the tool hits a word it has already seen, it drops the later copy and keeps the earliest, in the exact spot where it first landed. Feed it banana apple banana cherry apple and what comes back is banana apple cherry, because banana stays at the front, apple holds its second slot, cherry stays third, and the two trailing repeats are gone. A tool that sorted the output would hand you apple banana cherry, the same three words, but the flow of whatever you actually wrote is wrecked. For real writing, order is the whole point, so this tool never reorders.

Keeping the FIRST copy is the right default because the first time you use a word usually carries the meaning, with everything after it an accidental repeat. So the structure of your sentence survives and only the duplicates get trimmed.

Ignoring case or punctuation only changes what the tool compares, never what it writes back. Give it Apple apple APPLE with case-insensitive on and you get Apple, because Apple came first and it keeps that casing. Turn Ignore punctuation on and dog, dog cat! cat comes back as dog, cat!, since each word survives in whatever punctuated form it first appeared in. The comparison stays loose so it catches the repeats, but whatever it writes back is the literal original.

A token that is nothing but punctuation, like !!! or --, trips up a lot of quick tools. Strip the punctuation off those for comparison and they both reduce to nothing, and a naive tool would call them duplicates of each other and quietly eat your dashes and ellipses. This one keeps every punctuation-only token instead, because it cannot honestly tell one apart from another. It never deletes content you did not ask it to.

Sometimes you want casing to matter, and that is what the checkbox is for. In code, userId and UserId and userid can be three genuinely different names, and merging them would be a real bug. Turn case-insensitive off and the tool switches to exact matching, so any casing difference counts as a different word. Leave it on for most text, and turn it off when you are deduping code.

Comma-separated lists collect duplicates fast. Tag fields, category pickers, the keywords box in a CMS, a column pasted out of a spreadsheet, they all pick up repeats because people append without checking what is already there. Switch the separator to Commas and the tool splits on commas, trims the stray spaces around each item, and drops the empty slots a double comma or trailing comma leaves behind. So red, green, red, blue, green, becomes red, green, blue, ready to paste straight back.

Comma mode also treats a multi-word entry as one unit, which is exactly what a tag list needs. New York, Los Angeles, New York collapses to New York, Los Angeles, and "New York" is compared and kept whole instead of being torn into "New" and "York". Because each item gets trimmed first, inconsistent spacing like red,green, red still dedupes correctly.

Old copy or an AI draft that repeats "affordable" nine times in one paragraph is keyword stuffing, and these days that is an SEO liability rather than a trick. Run that paragraph through in Spaces mode and watch the removed-count climb. You do not publish the deduped output, stripping every repeat would gut normal grammar, since "the" and "and" and "you" are supposed to recur, so the number is better read as a diagnostic. A big removed-count on a short paragraph means you have been repeating yourself, so you go back to the original and rewrite by hand. The tool just shows you how much you repeated, and you go fix the prose.