Compare data from two columns or sheets

The Compare Columns or Sheets tool from the Remove Duplicates add-on for Google Sheets scans two columns or sheets of your choice (within one spreadsheet only) for duplicated or unique data. The results can be colored, deleted, copied, or moved to another location.

• Video: How to compare Google Sheets for duplicates
• Before you start
• How to use Compare Columns or Sheets
  • Start the tool
  • Step 1: Select your main table
  • Step 2: Choose the table for comparison
  • Step 3: Decide what to find
  • Step 4: Pick the columns to compare
  • Step 5: What to do with the results
  • See the result

Before you start

We care about your data and suggest you always create backup copies of your spreadsheets. A special option of the add-on will do that for you if you select it.

Please bear in mind that Google Sheets limits the total number of possible cells in your file up to 5 million cells.

How to use Compare Columns or Sheets

Start the tool

Find Remove Duplicates in the Add-ons menu and click on the Compare columns or sheets tool to open it:

Step 1: Select your main table

Choose the sheet and the range with your main table:

You can choose any of the open sheets in the Select the main sheet drop-down list.

The add-on highlights the entire used range in the sheet of your choice automatically and shows it in the Select your column or table field. You can alter it by changing the selection manually, entering the range address in this field, or by clicking the Select range icon. You will then see a corresponding dialog box that will let you pick the necessary cells:

You can choose to back up the original table by ticking off the Create a backup copy of the sheet checkbox.

Click Next to proceed to the second step.

Step 2: Choose the table for comparison

Choose the sheet with the table you want to compare to your main one:

You can choose any of the open sheets in the Select the second sheet drop-down list.

The Select your second column or table field shows the currently highlighted range. Define another one in this field by entering it on your keyboard, picking it directly in the sheet, or by using the Select range icon. The latter will open a dialog box so you could pick the necessary cells:

In case you want to change the main table/column, click the Back button.

Otherwise, choose Next to proceed to the next step.

Step 3: Decide what to find

The add-on allows you to find singular or repeating values in the tables:

• Pick Duplicate values to look for the records you have in both tables/columns:
  
  Note. The found records will be identified in the main sheet.
• Choose Unique values to find those entries that are in your main table only:
  

Click Next to go on to the next step.

Step 4: Pick the columns to compare

On this step, you will see a list of columns in your main table. Select the checkboxes next to the key columns you want to compare in your sheets and pick the corresponding column in your second table.

Tip. If you select more than one column, a row will be considered duplicate if the values in all these columns are the same.

1. If your tables have header rows, make sure to tick off the checkboxes Table 1 has headers and Table 2 has headers respectively to see the column titles. If you don't have headers, unselect these boxes to display column names.
2. You can use the 1st row content fields to see what kind of data you have in your main table columns.
3. If you want to look for complete row duplicates, select all columns by using this checkbox in the header row.
4. Automatically select all columns that have the same headers in both tables by using the Auto detect button.
5. Check the Skip empty cells box to ignore duplicated blanks in the selected columns. Otherwise, blank matches will be considered duplicates.
6. Use the Match case option to consider those records that differ only in case as uniques.
7. Make sure to indicate the corresponding Table 2 columns by clicking the down arrow for each of them and picking the necessary column from the drop-down list.

Once everything is set, press Next to proceed to the last step.

Step 5: What to do with the results

There are six ways to deal with the found values:

• Color the rows with the found values by picking the Fill with color option. Click on the down arrow next to this option to choose a hue you'd like to use.
• Add a status column to your main sheet:
  
  Tip. You'll be able to sort out duplicates easily after that.
• Decide to Copy to another location and have the results in a new sheet, new spreadsheet, or another existing sheet in the current file.
  Tip. The Existing sheet option lets you pick the necessary sheet from the list and specify a destination cell or a range:
  
  If you click the Select range icon, you'll be able to pick the top-left cell for the result directly from the sheet:
  
• The same goes for the Move to another location option. The values will be cut and pasted to a place of your choice.
• Pick Clear values to remove the found records in the selected columns and leave all other data intact.
• You can also remove all rows with the found dupes using the Delete rows within selection option.

Сlick Finish to find duplicate or unique values and mark them on the main sheet.

See the result

Once the add-on completes the search, you will see the summary of the results with the number of found values and the action that was applied to your main table: