Compare Two Lists finds the entries that occur only in List A, only in List B, in both lists, or anywhere across the two inputs. The comparison runs locally in your browser, so pasted and uploaded data is not sent to a server.
Paste values into the two editors, upload plain-text files, or drag files directly onto either list. Results update immediately as the input or list contents change.
How the list comparison works
Each input is first split into items using its selected separator. New lines are the default, but comma-, tab-, semicolon-, colon-, pipe-, equals-, slash-, dash-, percent-, period-, and backslash-separated data are supported as well.
The toolbar can trim surrounding whitespace, discard blank items, and remove duplicates as one-time cleanup actions. Each action rewrites the selected input so the resulting list remains visible. Sorting is applied to the parsed comparison output.
Understanding the results
- A only contains items found in List A but not matched in List B.
- Intersection (A ∩ B) contains items shared by the two lists.
- B only contains items found in List B but not matched in List A.
- Union (A ∪ B) combines List A with unmatched items from List B.
Repeated values are compared by occurrence count until you apply Remove duplicates. For example, two copies in List A and one copy in List B produce one shared copy and one A-only copy.
Useful comparison options
Use Trim spaces when lists come from spreadsheets, logs, or formatted documents. Remove empty items deletes empty records created by repeated separators. Remove duplicates keeps the first occurrence of each item. These controls run once when clicked and do not remain active.
The sort menu supports alphabetical, reverse alphabetical, length-based, and numeric ordering. Sorting changes the displayed order without changing which values match. The swap control exchanges both input text and the processing settings assigned to List A and List B.
Common uses
- Compare keyword, domain, URL, email, SKU, or identifier lists
- Find additions and removals between two exports
- Check access lists, configuration values, or inventory records
- Clean CSV, TSV, log, and plain-text data before further processing