DUPLICATE WORD FINDER
Find and remove duplicate words online with 30-color highlighting
Everything runs locally in your browser. Your data never leaves your device - no uploads, no servers, no server processing.
All processing happens directly on your machine using JavaScript. Close the tab and all text data is gone.
Drop files here or start typing
Duplicate words found
How to find duplicate words
Find and remove repeated words in your text in 3 steps
Full Documentation DocsInput text
Type, paste, or upload your document
Find duplicates
See duplicates highlighted in real-time
Clean & Export
Remove duplicates and download report
Why choose this word finder?
30-color highlighting with O(n) frequency analysis, one-click removal and export
Color-coded detection
30 distinct colors for duplicate words with overlay highlighting. Skips first occurrence and uses cursor-safe technique.
Smart detection
Advanced algorithms detect exact and case-insensitive duplicates with customizable sensitivity settings.
One-click cleaning
Remove all duplicate words instantly while preserving your text structure and formatting.
Detailed analytics
Duplicate ratio, cleanliness score, word frequency, keyword density and reading level - all calculated in real time.
File support
Drag & drop support for TXT, MD, CSV, JSON, TSV, HTML, XML, CSS, JS, SQL, DOCX, ODT, and LOG files.
Export reports
Download detailed analysis reports with cleaned text in multiple formats.
Frequently Asked Questions
Common questions about duplicate word detection
How does duplicate detection work?
This tool scans each word using hash-based frequency analysis and identifies exact matches. Toggle between case-sensitive and case-insensitive detection based on your needs.
What file formats can I upload?
You can upload TXT, MD, CSV, JSON, TSV, HTML, XML, CSS, JS, SQL, DOCX, ODT, and LOG files. Simply drag and drop or click to browse.
Can I remove duplicates automatically?
Yes! Click the clean button to automatically remove all duplicate words while preserving your text structure and formatting.
How is the duplicate ratio calculated?
The duplicate ratio shows the percentage of words that appear more than once in your text, helping you assess content quality.
Is my text stored anywhere?
No. All processing happens locally in your browser. Your text is never sent to any server and remains 100% private.
Can I export my analysis results?
Yes. Export reports with cleaned text, duplicate statistics, and word frequency analysis in TXT, CSV, MD, JSON, or DOCX format.
Technical Details
How this duplicate word finder detects and highlights repeated words
Detection Algorithm
This duplicate word finder uses hash-based frequency analysis with O(n) time complexity to scan text for repeated words. The algorithm builds a word frequency map in a single pass, then identifies consecutive and scattered duplicates separately. Case-insensitive matching ensures "The" and "the" are counted as the same word.
Analysis Depth
The find duplicate words tool distinguishes between consecutive duplicates (back-to-back repetitions) and scattered duplicates (words appearing multiple times throughout the text). Each duplicate is highlighted inline with color-coded markers showing exact positions. Frequency statistics display occurrence count and percentage for every repeated word.
Smart Filtering
Configurable sensitivity settings let you ignore common words (articles, prepositions, conjunctions) to focus on meaningful repetitions. The duplicate word checker processes Unicode text with full diacritic support and handles 13+ file formats including TXT, MD, CSV, JSON, TSV, HTML, XML, CSS, JS, SQL, DOCX, ODT, and LOG. DOCX extraction via Mammoth.js, ODT via JSZip. All analysis runs client-side in your browser.
Export & Cleanup
Export detailed analysis reports in TXT, CSV, MD, JSON, or DOCX format with duplicate statistics, word frequency tables, and cleaned text output. The repeated word finder provides one-click duplicate removal with before/after comparison. Auto-save via IndexedDB preserves your text and analysis across browser sessions.
Text Transformation Tools
Eight built-in text tools: trim whitespace, remove line breaks, lowercase, uppercase, title case, remove extra spaces, sort lines alphabetically, and reverse text. Find and Replace supports case-sensitive and whole-word matching with wrap-around navigation. Undo and redo with a 50-state history stack.
Auto-Save and Persistence
Text and analysis auto-save every 500ms via IndexedDB with visual save status indicator. All data persists across browser sessions with zero server dependency. Fullscreen focus mode provides a distraction-free editing environment with the same duplicate detection and highlighting features.