In Excel: use =A2=B2 for row-by-row matches, or =COUNTIF($B:$B,A2)>0 to check whether each value in column A appears anywhere in column B.
On this page7
Only in A: 2 · Only in B: 1
What this does
Comparing columns has two different meanings. Row-by-row comparison asks whether A2 equals B2, A3 equals B3, and so on. List comparison asks whether each value from one column exists anywhere in the other column. The first uses a direct equality test; the second uses COUNTIF, MATCH or XLOOKUP. Most people learn this as a sequence of clicks and forget it by next week; learning it as a pattern instead is what lets you apply it to the next, slightly different version of the problem without starting from scratch. That is the difference this page is trying to make. The difference between a quick fix and a sheet you can trust is the extra minute you spend validating “compare columns in excel”. Start on a copy or a tiny sample, keep the affected columns visible, and compare the result with the tool above before you touch the real workbook. When a formula is involved, keep the inputs labelled beside it, reference cells instead of typing values, and apply number formatting only after the result checks out. The point is a layout choice that keeps the sheet readable and sortable, but the practical win is that someone else can open the file and understand what happened without asking you.
A worked example
Column A has invoice IDs from system 1 and column B has IDs from system 2. In C2, =A2=B2 returns TRUE only when the two rows match exactly. If the rows are not aligned, use =COUNTIF($B:$B,A2)>0 in C2; invoice 1042 returns TRUE if it appears anywhere in B, even on a different row. Column comparison is core spreadsheet reconciliation: invoices, IDs, email lists, product codes, migration checks and any workflow where two systems should agree. One habit worth forming early: name the cells that hold your inputs, so the formula reads in plain language instead of a string of cell addresses. A reviewer — or you in three months — can then follow the logic without decoding what B7 and D2 were supposed to mean, which is most of what makes a sheet maintainable.
In Google Sheets
Everything above works in Google Sheets too. Excel and Sheets share the formula syntax used here; only the surrounding menus are arranged differently. That portability is deliberate — learn it once and it follows you between the two tools and across Windows and Mac. The aim was to get you unstuck fast and leave you a little more capable than a copy-paste would. The answer is at the top, the tool proves it, and the detail above shows why it holds — so the next time a colleague asks, you can answer without reaching for search. If you take one thing from this page on “compare columns in excel”, make it the habit rather than the keystrokes: set the problem up with labelled inputs, reference those cells, and let Excel do the recomputing. Bookmark the page for the syntax, but do the example once in a blank sheet and check it against the tool above — five minutes of hands-on practice fixes the method in memory far better than re-reading, and it surfaces the small snags while they are still harmless. After that the technique is genuinely yours: faster than searching for it again, and reliable enough to drop into work that other people depend on.
Common mistakes
- Using
=A2=B2when the two lists are sorted differently. - Forgetting absolute references in $B:$B, so the lookup range shifts while copying.
- Treating numbers stored as text as equal to real numbers without cleaning the data.
- Ignoring leading/trailing spaces;
TRIMboth columns when matches look visually identical but fail.
Frequently asked questions
How do I compare two columns row by row?
Use =A2=B2 and fill down. TRUE means the values in that row match exactly.
How do I find values in A that are missing from B?
Use =COUNTIF($B:$B,A2)=0 and filter TRUE results.
Can conditional formatting compare columns?
Yes. Use a formula rule such as =$A2<>$B2 for row differences, or COUNTIF for list membership.
Other ways people ask this
People reach this page typing “how to compare columns in excel”, “column compare excel”, “compare to columns in excel” and “how to compare to columns in excel”, among other phrasings; whichever wording you used, the fix above is the one you want.
Why do people search for this in so many different ways?
Because the same task has many names. “how to compare columns in excel”, “column compare excel”, “compare to columns in excel” all point at the one operation explained on this page, which is why they all lead here.