Compare lists
Find items in both lists or only one list, with case and whitespace options and three downloadable results.
How it works & useful details
How to use this tool
Paste one item per line into each list. Get the common items and the items unique to either list; download each result or all three as a ZIP.
How the result is calculated
Each result contains unique items, preserving their first appearance. Common items use the first list’s spelling. Trim item edges changes output as well as matching. Ignoring blank items also skips whitespace-only lines. Case-insensitive matching uses Unicode lowercasing; accents and composed/decomposed spellings remain distinct.
Line tools normalize CRLF and CR to LF. A final newline represents an empty final line; empty input has zero lines.
Up to 500,000 UTF-16 code units per input. Text stays on your device.
About this tool
Compare lists finds the items that appear in both lists or only in one of them, which answers common de-duplication and reconciliation questions. Case and whitespace handling can be adjusted so the comparison matches your data.
Three separate results are produced: the shared items, the items unique to the first list, and the items unique to the second. Everything runs locally, and each result can be downloaded.
How to use it
- Paste the first list, one item per line.
- Paste the second list.
- Set the case and whitespace comparison options.
- Review the shared and unique results and download what you need.
Worked example
First list: [email protected], [email protected], [email protected]. Second list: [email protected], "[email protected] " with a trailing space, and [email protected]. With trimming and case-insensitive matching enabled, the result is:
IN BOTH LISTS
[email protected]
[email protected]
ONLY IN FIRST LIST
[email protected]
ONLY IN SECOND LIST
[email protected]Without those options, Bob and "carol " would not match their counterparts, and both lists would appear to have three unique entries. Common items are shown with the first list's spelling.
Common uses
- Finding newsletter subscribers who are missing from a CRM export, or the reverse.
- Checking which SKUs from a supplier list are not in your catalogue.
- Comparing two dependency lists, server inventories, or user permission exports.
- Reconciling an attendee list against registrations.
The comparison treats each list as a set of distinct items, so duplicates within one list are reported once. Each of the three results can be downloaded separately, or all together as a ZIP.
Frequently asked questions
How are duplicate items within a list handled?
Each list is treated as a set for the comparison, so repeated items do not multiply the results.
Does order matter?
No. Results are based on which items exist in each list, not on their position.
What is the limit?
Up to 500,000 characters across both lists.
Are accented and unaccented letters treated as equal?
No. Case-insensitive matching ignores letter case only. "José" and "Jose" remain different items.