Compare values without a spreadsheet formula
Paste one column on each side and see what appears in both, only in A, only in B, or anywhere across the two lists. This is useful for one-off reconciliation jobs where VLOOKUP, XLOOKUP or MATCH would be more setup than the task deserves.
Keep the useful subset
Each result tab can become the current TaskThimble list. That means “Only A”, “Only B”, the union or the intersection can continue directly into sorting, deduplication, counting or other list tools without copy-paste.
Matching rules are visible
Small formatting differences can change a comparison. TaskThimble lets you decide whether surrounding spaces are trimmed, empty lines are ignored and letter case matters. The active rule is shown with the result instead of being applied silently.
Duplicates are separate from differences
A value can occur in both columns and still be duplicated on one side. Use the duplicate tabs to find repeated values without confusing them with values that are genuinely missing.
When to use CSV Compare instead
If each item has several fields—such as customer ID, name, plan and status—use CSV Compare. It matches complete records by a key and can show which cells changed.