
Validating your data as you type can prevent any surprises when you are doing analysis / follow-up on the data. Thankfully, excel has the right tools to do it. Excel drop down list can assist you in picking up a value from a valid list to enter in a cell. Here is a short how-to guide to get you started on data validation in excel.
Howto set up Drop Down list in Excel?
- First, set up a list of valid values in range of cells. Say your valid list of entries is in A1:A6.
- Now go the cell where you want to validation drop down to appear.
- Go to Data ribbon and click on Validation
- Set up “List” as allowed values and enter =A1:A6 as Source (see below picture)
- Done. Now you can see the drop-down in your cell.

Video – How to create Drop Down List in Excel & Best Practice Tips
I made a video with a real world example of drop down lists. Please watch it below to understand the set up process & how to customize the validation rules.
Sample workbook to Practice Data Validation Drop Downs
Click here to download the sample workbook to practice data validation drop down lists.
How-to ignore duplicates while setting up validation list?
If you want to use a source list that has duplicates and want to ignore them when setting up validation drop-down, then you have two options. Something like this:

- Use Excel Dynamic Arrays (works in Excel 365)
- Use Pivot Tables (works in all versions of Excel)
Let’s say your list of inputs is in customers[Education] column.
Using Dynamic Arrays
Note: This works only in Excel 365 with dynamic array feature. Not all 365 users will have access to DA now, but everyone of them will get Dynamic Arrays soon.
Just go to an empty cell (preferably in a separate worksheet like settings tab) and type =SORT(UNIQUE(customers[Education]))
Excel will spill your data down to next few cells depending on how many unique values are in your data.
Let’s say your formula is in cell A1
Now, go to Formulas > Define Name and create a name for validation options as,

Finally, use myOptions as list source for data validation.
Using Pivot Tables for drop down without duplicates
This is most compatible option as it works in all versions of Excel.
- In a new sheet or blank range, insert a pivot table from your data.
- Add the Education field to row labels area
- Remove any grand, sub-totals
- Let’s say the first item in the pivot is in cell A2.

Now, create a name with myOptions and use the formula
=OFFSET($A$2,0,0, COUNTA($A$2:$A$21), 1)
this will make a dynamic named range with how many ever education options are there in that pivot table.
Note: Change $A$21 to a cell address further down if you will have more options.
Finally, use myOptions as the list source for data validation.
Your drop-down list without duplicates will be ready.
Drop-down list without duplicates – Video
I made a video explaining how to make dropdowns without duplicate values. You can see a cameo from Nishanth (my son) in the video. Check it out if you want to understand how Dynamic Array method and Pivot Table method can be setup. Watch it below or visit my YouTube Channel.
Best Practice for Drop-downs
Drop-downs are very useful for data analysis, charting and reporting work. They are user friendly and easy to set up. That said, keep these ideas in mind when implementing them.
- Use named ranges: Instead of hard-coding cell addresses, use named ranges for setting up validation lists. This will also enable you to connect data validation list to table columns thru structural references.
- Source lists in a separate tab: Whenever possible, set up all your source lists in a separate tab. I call mine “Settings”. This will make any changes easy for you.
- Don’t have too many options: If your drop-down is having more than 50 options, consider two-level cascading drop-downs or some other way to gather inputs.
- Try Form controls or Slicers too: Drop-downs are great, but they are just one of the many ways to add interactive abilities to your workbooks. Consider form controls and Slicers too.
Download Practice Workbook
I made a workbook with simple and “avoiding duplicates” examples. Please download it here and practice to learn more about these techniques.
More Data Validation Tricks
Here is a collection of useful tricks and ideas with Data Validation. Check them out to learn more.














11 Responses to “Fix Incorrect Percentages with this Paste-Special Trick”
I've just taught yesterday to a colleague of mine how to convert amounts in local currency into another by pasting special the ROE.
great thing to know !!!
Chandoo - this is such a great trick and helps save time. If you don't use this shortcut, you have to take can create a formula where =(ref cell /100), copy that all the way down, covert it to a percentage and then copy/paste values to the original column. This does it all much faster. Nice job!
I was just asking peers yesterday if anyone know if an easy way to do this, I've been editing each cell and adding a % manually vs setting the cell to Percentage for months and just finally reached my wits end. What perfect timing! Thanks, great tip!
If it's just appearance you care about, another alternative is to use this custom number format:
0"%"
By adding the percent sign in quotes, it gets treated as text and won't do what you warned about here: "You can not just format the cells to % format either, excel shows 23 as 2300% then."
Dear Jon S. You are the reason I love the internet. 3 year old comments making my life easier.
Thank you.
Here is a quicker protocol.
Enter 10000% into the extra cell, copy this cell, select the range you need to convert to percentages, and use paste special > divide. Since the Paste > All option is selected, it not only divides by 10000% (i.e. 100), it also applies the % format to the cells being pasted on.
@Martin: That is another very good use of Divide / Multiply operations.
@Tony, @Jody: Thank you 🙂
@Jon S: Good one...
@Jon... now why didnt I think of that.. Excellent
Thank You so much. it is really helped me.
Big help...Thanks
Thanks. That really saved me a lot of time!
Is Show Formulas is turned on in the Formula Ribbon, it will stay in decimal form until that is turned off. Drove me batty for an hour until I just figured it out.