Compare Two Lists
Compare two lists and instantly see what is missing, what is extra, and what they have in common. Paste one item per line, from a spreadsheet column, an export, or an email, and the comparison runs in your browser with nothing uploaded.
Find differences between two lists in seconds
Comparing two lists by eye stops working past a few dozen items. This tool treats each line as one item, normalises it according to the options you pick, and sorts every distinct item into one of three groups: only in A (in the first list but missing from the second), only in B (new or extra items), and in both (the overlap). Typical jobs: which customers did not renew, which files are missing from a backup, which emails are on one mailing list but not the other, or which SKUs disappeared between two exports.
Why "identical" items fail to match
Most failed comparisons are not about the data, but about invisible characters. A trailing space turns "Smith " into a different item from "Smith". Text copied from a web page often contains non-breaking spaces (character 160), which look exactly like normal spaces and which Excel's TRIM function does not remove. Exports mix "ACME" and "Acme". Trim spaces strips surrounding whitespace and converts non-breaking spaces before comparing, and Ignore case folds capitalisation. Both only affect how items are matched; the results show your original text.
Compare two Excel columns without formulas
In a spreadsheet, finding what is missing usually means a COUNTIF or XLOOKUP formula, filled down and filtered. That works, but it is fiddly for a one-off check and easy to get wrong when the data has stray spaces or numbers stored as text. Instead, copy a column from Excel or Google Sheets, paste it here as List A, do the same for List B, and copy whichever result you need straight back into your sheet. For the formula approach, and the clean-up steps that make it reliable, see how to compare two lists and find what is missing.
Related tools
To clean a single list first, remove duplicate lines or sort it alphabetically. To compare two versions of the same document, where order and wording matter, use text compare, which highlights changed lines and words. Everything runs on your device, so private lists stay private.
Frequently asked questions
How do I compare two lists to find differences?
Paste one list into List A and the other into List B, one item per line. The tool instantly shows three results: items only in List A, items only in List B, and items in both. Each result has its own count and copy button.
Why do two items that look the same not match?
Usually because of invisible differences: trailing spaces, non-breaking spaces copied from a web page, tabs, or different capitalisation. "Trim spaces" removes surrounding whitespace and converts non-breaking spaces before comparing, and "Ignore case" treats "Apple" and "apple" as the same item.
Does the order of the lists matter?
No. Items are matched wherever they appear, so the same item at line 3 of one list and line 300 of the other counts as a match. Results keep the order in which items first appear in your list.
What happens to duplicates inside one list?
Each result lists every distinct item once, so duplicates within a list do not inflate the counts. The status line tells you how many duplicate lines were found in each list, in case the duplicates themselves are the problem.
Can I compare two Excel columns with this?
Yes. Copy each column in Excel or Google Sheets and paste it into List A and List B; every cell becomes one line. It is often quicker than writing COUNTIF or XLOOKUP formulas, and nothing is uploaded.
Is my data uploaded anywhere?
No. The comparison runs entirely in your browser, so customer lists, email addresses, and internal IDs never leave your device.
Related reading
- How to Compare Two Lists and Find What's Missing
The formulas for Excel and Google Sheets, the invisible characters that break matches, and a paste-and-go alternative.