Compare Two Lists / Arrays
Compare two lists or arrays online. Find items only in A, only in B, and common items. Free, fast, client-side tool with count statistics.
Why Use the List Comparison Tool?
Comparing two lists manually is error-prone and time-consuming, especially with large datasets. Our List Comparison Tool instantly identifies unique items in each list and shared items between them, making it invaluable for data analysis, inventory management, and quality assurance tasks.
Key Features
- Three-way comparison: items only in A, only in B, and common to both
- Automatic deduplication of results for clean output
- Real-time statistics showing unique and total item counts
- One-click copy for each result section
How to Use
- Paste or type your first list in the List A textarea
- Paste or type your second list in the List B textarea
- View instant results: only-in-A, common, and only-in-B items with counts
Technical Details
This tool uses JavaScript Set operations for O(n) comparison performance. Items are compared using strict equality. Each input line is treated as a separate item, with blank lines ignored. All processing runs entirely in your browser — no data is ever sent to a server.
FAQ
Is the comparison case-sensitive?
Yes, the comparison is case-sensitive by default. 'Apple' and 'apple' are treated as different items.
Duplicates in the input are automatically deduplicated in the results. Each item appears at most once in each output section.
Duplicates in the input are automatically deduplicated in the results. Each item appears at most once in each output section.
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