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Duplicate analyzer
Find duplicate lines, count occurrences and export a clean summary. Processing stays local in your browser.
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- Works offline
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Result
Why use this tool?
Analyze a list to find repeated lines, count occurrences, and quickly identify the values that appear most often. It is useful before data cleanup, deduplication, or quality checks on lists copied from spreadsheets or exports.
Smart processing
Clean, structure, and transform your data with rules tailored to the format being processed.
Supported formats
CSV, XLSX, and other tabular formats depending on each tool’s capabilities.
Save time
Get a clean, ready-to-use result in seconds without installing software or configuring a complex workflow.
Guide
How to use this tool
- 1
Paste the list to analyze
Add one item per line in the input area.
- 2
Run duplicate analysis
The tool groups identical lines and counts how many times each one appears.
- 3
Review repeated values
Identify the most frequent duplicates and reuse the summary for cleanup or validation.
Tips and best practices
- Normalize letter case and whitespace first if values such as 'Paris', 'paris', and 'Paris ' should count as the same item.
- Before removing duplicates, confirm that repeated values are not legitimate in your business context.
- For larger structured datasets, a CSV tool may be more appropriate when you need to compare multiple columns.
Frequently asked questions
What is the difference between analyzing and removing duplicates?
Analysis counts and highlights repetitions without changing the source list. Removal creates a deduplicated list.
Are case differences always treated as identical?
That depends on the processing rules. Normalize case first if you want variants such as 'Paris' and 'paris' grouped together.
Can I analyze values copied from a spreadsheet?
Yes, when they are pasted as one item per line. For multi-column tables, use a dedicated tabular-data tool instead.
Is my data uploaded to a server?
No. Analysis runs locally in your browser.
Was this tool useful?
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