The question from the Reddit user cuts to the heart of what makes spreadsheets both powerful and frustrating. They want to compare two columns and spot a single missing or extra figure. That is a simple ask, yet traditional formulas often turn it into a puzzle of nested functions and brittle logic. Our take is clear: this does not need to be complicated. The right formula should be as adaptable as the data itself.
For Google Sheets, the most direct solution is =FILTER(A:A, ISERROR(MATCH(A:A, B:B, 0))). This returns the value in column A that has no match in column B. To find the extra figure in B, swap the ranges: =FILTER(B:B, ISERROR(MATCH(B:B, A:A, 0))). The beauty of this approach is that it handles unsorted lists, repeated values, and varying row counts without manual adjustment. No array formulas, no helper columns. Just a clean, readable expression that does exactly what you ask. Would the formula differ for Excel? Yes, because Excel lacks the FILTER function in older versions. In Excel 365, you can use the same syntax. For earlier versions, the equivalent requires =INDEX(A:A, MATCH(TRUE, ISERROR(MATCH(A:A, B:B, 0)), 0)) entered as an array formula with Ctrl+Shift+Enter. That works, but it is less intuitive and harder to maintain.
This difference matters because it reveals a deeper truth about the tools we choose. Google Sheets was built with collaboration and simplicity in mind, so its formula language prioritizes readability and directness. Excel, with its legacy of desktop-first design, often demands more steps to achieve the same result. The user who asked this question is not looking for a theoretical debate about platform superiority. They want a practical answer that saves time and reduces errors. The formula we recommend does that, but it also points toward a larger shift: the most effective spreadsheet solutions are those that let you focus on the problem, not the syntax.
What this means for you is that the barrier to solving data comparison tasks is lower than you might think. You do not need to memorize obscure functions or debug complex logic. A single, adaptable formula can handle the job across different platforms with minimal adjustment. The next time you face a mismatch between two columns, resist the urge to manually scan or build a fragile VLOOKUP chain. Reach for FILTER or its Excel equivalent. Let the tool do the heavy lifting, so you can spend your energy on what the data actually tells you.