Sets
Four answers at once
Only in A, only in B, in both, and the combined unique list — each with a count, copy and download.
List Diff Checker · Free
Compare two lists in one click.
Find what's missing, what's shared and what's duplicated — for emails, IDs, SKUs, names or any column you copy from a spreadsheet.
Results appear here.
Paste two lists to compare them
Find what's missing from each list, what they share, and duplicates — emails, SKUs, IDs, names, anything.
Only in List A
Only in List B
In Both Lists
All Unique Items
How It Works
Three steps. No sign-up.
- 1
Paste your first list into List A and your second into List B — one item per line, or separated by commas, semicolons or tabs.
- 2
Press Compare Lists. Separators are detected automatically; choose whether to ignore case and extra spaces.
- 3
Copy or download what’s only in A, only in B, in both, or all unique items combined.
Features
Built for real-world data.
Clean
Case & space aware
Ignore case for emails and names, trim stray spaces, and skip blank lines so matches are real matches.
Dupes
Duplicates flagged
Repeated items in either list are listed so you can clean up your data before importing it.
Flexible
Any separator
Lines, commas, semicolons, tabs or spaces — detected automatically, or choose one yourself.
Sort
Natural sorting
Keep the original order or sort A→Z with natural number ordering (item2 before item10).
Private
Nothing leaves your device
Email lists and customer IDs are compared locally in your browser, never uploaded.
FAQ
Questions & answers
How do I find items that are in one list but not the other?
Paste both lists and press Compare Lists. “Only in List A” shows items missing from B, and “Only in List B” shows items missing from A.
Can I compare two columns from Excel?
Yes. Copy a column from Excel or Google Sheets and paste it into each box — each cell becomes one item.
Is the comparison case-sensitive?
By default, yes. Turn on “Ignore case” to treat “Ana@Acme.com” and “ana@acme.com” as the same item.
What happens to duplicates?
Results contain each item once. Duplicates found in either input are reported below the results so you can review them.
How many items can I compare?
Hundreds of thousands of items compare in well under a second, since everything uses fast in-browser set operations.
Is my list uploaded?
No. The comparison runs entirely in your browser and history is kept only on your device.
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