How do I remove duplicates in Excel without losing data?

Excel's Remove Duplicates button deletes rows permanently and in place, so work on a copy of your sheet first. To keep the original, copy the column or table to a new sheet, run Remove Duplicates there, or use a COUNTIF helper column to flag duplicates so you can review them before deleting anything.

How do I find duplicates without deleting them?

Use Conditional Formatting. Select the range, go to Home → Conditional Formatting → Highlight Cells Rules → Duplicate Values. Excel highlights every duplicate so you can inspect them. Alternatively, add a helper column with =COUNTIF(A:A, A2) — any value greater than 1 appears more than once.

Does Remove Duplicates keep the first or last copy?

Excel's Remove Duplicates always keeps the first occurrence in row order and deletes the later copies. If you need to keep the last copy instead, sort the data so the row you want to keep appears first, or use a tool that lets you choose first or last explicitly.

Why is Remove Duplicates not working in Excel?

The most common cause is invisible differences: trailing spaces, different letter case treated as identical, or numbers stored as text. Excel matching is case-insensitive but space-sensitive. Clean the column with TRIM first, or use a tool that lets you ignore case and surrounding spaces when matching.

How do I remove duplicates across multiple columns?

In the Remove Duplicates dialog, tick every column that together defines a unique record. A row is treated as a duplicate only when the values in all of the ticked columns match another row. Untick columns that should not affect the comparison, such as a notes or timestamp field.

How do I remove duplicates in Excel based on one column?

In the Remove Duplicates dialog, untick every column except the one that defines a unique record — for example, Email. Excel then treats two rows as duplicates whenever that single column matches, keeps the first occurrence, and deletes the rest even when the other columns differ. This is the right setting when one field is the true identity of a row and everything else is supporting detail.

How do I count how many duplicates are in Excel before removing them?

Add a helper column with =COUNTIF(A:A, A2) and drag it down: any result above 1 marks a repeated value. To get a single total, use =SUMPRODUCT((COUNTIF(A2:A100, A2:A100)>1)*1), which counts every cell involved in a duplicate. Checking the count first tells you how much the file will shrink, so the Remove Duplicates pass holds no surprises.

How to remove duplicates in Excel

To remove duplicates in Excel, select your data, open the Data tab, and click Remove Duplicates. Tick the columns that define a duplicate, then click OK — Excel keeps the first copy of each row and deletes the rest. For a faster, error-proof option, Sigmera removes duplicate rows from a CSV in one click, entirely in your browser with no upload.

Last updated: June 2026

Remove duplicates in Excel (the manual way)

Excel has a built-in Remove Duplicates command that deletes repeated rows in place. It is the fastest manual route and works in every modern version of Excel (2010 and later, plus Microsoft 365).

1. Select your data. Click any cell inside your table, or highlight the exact range you want to clean, including the header row.
2. Open the Data tab. On the ribbon, click Data, then click Remove Duplicates in the Data Tools group.
3. Choose the columns to match on. In the dialog, tick only the columns that define a duplicate. Tick My data has headers if your first row is a header so it is not treated as data.
4. Confirm and review. Click OK. Excel keeps the first occurrence of each row, deletes the rest, and reports how many duplicates were removed and how many unique values remain.

Find duplicates first with COUNTIF or Conditional Formatting

If you want to review duplicates before deleting them, add a helper column with =COUNTIF(A:A, A2) and drag it down. Any value greater than 1 appears more than once. Alternatively, select the range and use Home → Conditional Formatting → Highlight Cells Rules → Duplicate Values to colour every repeated entry without changing anything.

Remove duplicates in Google Sheets

Google Sheets has its own one-click command:

1. Select the range you want to deduplicate, including headers.
2. Open Data → Data cleanup → Remove duplicates.
3. Confirm headers and columns, then click Remove duplicates. Sheets reports how many rows were removed.

You can also use the formula =UNIQUE(A2:A) to spill a duplicate-free copy of a column into a new range, leaving the original untouched.

Faster way → do it in one click with the free Remove Duplicates tool, no upload. Choose first or last copy, ignore case and spacing, and preview every flagged row before you download.

Do this in 1 click — free

Once the sheet is deduplicated, most importers want plain text rather than a workbook. You can export the sheet to CSV in the same browser tab — no upload, and the UTF-8 output keeps accented names intact.

Manual Excel vs Sigmera, compared

Method	Time	Handles edge cases	Skill needed
Sigmera (this tool)	Seconds, one click	Ignore case & spacing, choose first/last copy, live preview	None
Excel Remove Duplicates	A minute (find the menu)	Space-sensitive; keeps first only; deletes in place	Low (menus)
COUNTIF formula	Several minutes	Flags only; you still filter and delete manually	Medium (formulas)

Frequently asked questions

How do I remove duplicates in Excel without losing data?: Excel's Remove Duplicates button deletes rows permanently and in place, so work on a copy of your sheet first. To keep the original, copy the column or table to a new sheet, run Remove Duplicates there, or use a COUNTIF helper column to flag duplicates so you can review them before deleting anything.
How do I find duplicates without deleting them?: Use Conditional Formatting. Select the range, go to Home → Conditional Formatting → Highlight Cells Rules → Duplicate Values. Excel highlights every duplicate so you can inspect them. Alternatively, add a helper column with =COUNTIF(A:A, A2) — any value greater than 1 appears more than once.
Does Remove Duplicates keep the first or last copy?: Excel's Remove Duplicates always keeps the first occurrence in row order and deletes the later copies. If you need to keep the last copy instead, sort the data so the row you want to keep appears first, or use a tool that lets you choose first or last explicitly.
Why is Remove Duplicates not working in Excel?: The most common cause is invisible differences: trailing spaces, different letter case treated as identical, or numbers stored as text. Excel matching is case-insensitive but space-sensitive. Clean the column with TRIM first, or use a tool that lets you ignore case and surrounding spaces when matching.
How do I remove duplicates across multiple columns?: In the Remove Duplicates dialog, tick every column that together defines a unique record. A row is treated as a duplicate only when the values in all of the ticked columns match another row. Untick columns that should not affect the comparison, such as a notes or timestamp field.
How do I remove duplicates in Excel based on one column?: In the Remove Duplicates dialog, untick every column except the one that defines a unique record — for example, Email. Excel then treats two rows as duplicates whenever that single column matches, keeps the first occurrence, and deletes the rest even when the other columns differ. This is the right setting when one field is the true identity of a row and everything else is supporting detail.
How do I count how many duplicates are in Excel before removing them?: Add a helper column with =COUNTIF(A:A, A2) and drag it down: any result above 1 marks a repeated value. To get a single total, use =SUMPRODUCT((COUNTIF(A2:A100, A2:A100)>1)*1), which counts every cell involved in a duplicate. Checking the count first tells you how much the file will shrink, so the Remove Duplicates pass holds no surprises.