Compare Two Lists

Find what overlaps and what is missing

Paste one item per line into List A and List B. Choose whether surrounding spaces and capitalization should matter, select the result you need, then press Compare lists. The summary counts all four groups; the output contains your selected group. Copy the result or download a TXT file.

Four different questions

In both lists finds the shared items. Only in A removes anything also found in B. Only in B finds entries absent from A. Combined unique list keeps every distinct item from either input. This is a membership comparison: moving an item to another line does not make it different. Use Text Diff Checker when the order of a document's lines matters.

Worked example: two shopping lists

List A contains Apples, Bread, Milk, and Apples again. List B contains Milk, Coffee, and Bread. The common items are Bread and Milk. Only in A contains Apples; Only in B contains Coffee. The combined unique list contains Apples, Bread, Milk, and Coffee. Apples appears once because repeated entries represent one member, not two separate purchases.

Matching rules

Trim surrounding spaces removes whitespace at each item's beginning and end before matching and displaying it. It does not collapse spaces inside an item. Ignore case compares lowercase forms, while output keeps the first encountered spelling. Blank or whitespace-only lines are always skipped. Matching is exact after those choices; punctuation, accents, and spelling differences are not treated as approximate matches.

Order and repeated items

Common and A-only output follow List A's first occurrence order. B-only output follows List B. The combined result starts with unique A entries, then adds previously unseen B entries. When Ignore case is enabled, Apple and APPLE count as the same member, with the first spelling retained. This is useful for membership checks but unsuitable when repeated quantities or occurrence counts carry meaning.

Assumptions and limitations

Each line is a complete item. Commas and tabs inside a line are ordinary characters, so pasting an entire spreadsheet row compares that row as one string. One list may be empty, but at least one nonblank item is required across both inputs. Combined input is limited to 100,000 lines and 2 million characters to keep processing manageable. All comparison takes place locally; the tool does not save or upload your lists.