How to Delete All Duplicate Values in Excel Sheet

What this does

Remove Duplicates strips repeated rows from a selection, keeping the first occurrence and deleting the rest in place. It judges duplicates only on the columns you tick, so two rows can differ elsewhere and still be removed. When you want a deduplicated copy without touching the source, the UNIQUE function spills a clean list you can refer back to. The same idea underpins a lot of everyday Excel work, so the few minutes spent getting it right here pay back across every sheet you build afterwards. Treat it as a pattern, not a one-off, and it stops being something you look up and starts being something you reach for. Treat “delete all duplicate values in excel sheet” as a small repeatable workflow rather than a one-off click you hope to remember next time. Use a small test block before the live file, so any surprise in the affected duplicates shows up while it is still harmless. When this is a ribbon command, the selection matters more than the button: confirm the range, apply the command, then spot-check the output before saving. That turns a data step that keeps your analysis trustworthy into a method you can reuse, explain, and defend when the workbook leaves your screen.

A worked example

A customer list in A1:C500 has repeats. Select it, choose Data ▸ Remove Duplicates, and tick only the Email column so rows are treated as duplicates when emails match. Excel reports how many it removed. Non-destructive alternative: in a blank cell type =UNIQUE(A2:C500) and a deduplicated copy appears, updating automatically as the source changes. Duplicate rows quietly inflate counts, totals and mailing lists. Removing them — or surfacing them with UNIQUE and COUNTIF — is a basic data-hygiene step before any analysis you want to trust. A practical tip: try it on a copy of the sheet or a handful of sample rows first and check the result before you apply it to the real data. That one habit catches almost every surprise while it is still cheap to reverse.

In Google Sheets

Some functions on this page are newer additions to Excel: they are in current Microsoft 365 and Excel for the web, while older perpetual Excel versions return #NAME?. Google Sheets maintains its own function list, so confirm each function exists there before relying on the same formula. 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. Here is the takeaway for “delete all duplicate values in excel sheet”: follow the steps at the top, check the result on the sheet itself, and keep undo in mind while you experiment. Done once deliberately, it becomes something you do from memory in Excel rather than something you search for again.

Common mistakes

• Selecting only one column, so Remove Duplicates shrinks that column out of step with its row.
• Forgetting it edits in place — make a copy first if you might need the duplicates back.
• Ticking every column when only one (like an ID) actually defines a duplicate.
• Overlooking stray spaces or case differences that stop true duplicates from matching; clean with TRIM first.

Frequently asked questions