totn Excel Functions

MS Excel: How to use the LOOKUP Function (WS)

This Excel tutorial explains how to use the Excel LOOKUP function with syntax and examples.

Description

The Microsoft Excel LOOKUP function returns a value from a range (one row or one column) or from an array.

The LOOKUP function is a built-in function in Excel that is categorized as a Lookup/Reference Function. It can be used as a worksheet function (WS) in Excel. As a worksheet function, the LOOKUP function can be entered as part of a formula in a cell of a worksheet.

There are 2 different syntaxes for the LOOKUP function:

LOOKUP Function (Syntax #1)

In Syntax #1, the LOOKUP function searches for value in the lookup_range and returns the value in the result_range that is in the same position.

The syntax for the LOOKUP function in Microsoft Excel is:

LOOKUP( value, lookup_range, [result_range] )

Parameters or Arguments

value
The value to search for in the lookup_range.
lookup_range
A single row or single column of data that is sorted in ascending order. The LOOKUP function searches for value in this range.
result_range
Optional. It is a single row or single column of data that is the same size as the lookup_range. The LOOKUP function searches for the value in the lookup_range and returns the value from the same position in the result_range. If this parameter is omitted, it will return the first column of data.

Returns

The LOOKUP function returns any datatype such as a string, numeric, date, etc.
If the LOOKUP function can not find an exact match, it chooses the largest value in the lookup_range that is less than or equal to the value.
If the value is smaller than all of the values in the lookup_range, then the LOOKUP function will return #N/A.
If the values in the LOOKUP_range are not sorted in ascending order, the LOOKUP function will return the incorrect value.

Applies To

  • Excel for Office 365, Excel 2019, Excel 2016, Excel 2013, Excel 2011 for Mac, Excel 2010, Excel 2007, Excel 2003, Excel XP, Excel 2000

Type of Function

  • Worksheet function (WS)

Example (as Worksheet Function)

Let's look at some Excel LOOKUP function examples and explore how to use the LOOKUP function as a worksheet function in Microsoft Excel:

Microsoft Excel

Based on the Excel spreadsheet above, the following LOOKUP examples would return:

=LOOKUP(10251, A1:A6, B1:B6)
Result: "Pears"

=LOOKUP(10251, A1:A6)
Result: 10251

=LOOKUP(10246, A1:A6, B1:B6)
Result: #N/A

=LOOKUP(10248, A1:A6, B1:B6)
Result: "Apples"

LOOKUP Function (Syntax #2)

In Syntax #2, the LOOKUP function searches for the value in the first row or column of the array and returns the corresponding value in the last row or column of the array.

The syntax for the LOOKUP function in Microsoft Excel is:

LOOKUP( value, array )

Parameters or Arguments

value
The value to search for in the array. The values must be in ascending order.
array
An array of values that contains both the values to search for and return.

Returns

The LOOKUP function returns any datatype such as a string, numeric, date, etc.
If the LOOKUP function can not find an exact match, it chooses the largest value in the lookup_range that is less than or equal to the value.
If the value is smaller than all of the values in the lookup_range, then the LOOKUP function will return #N/A.
If the values in the array are not sorted in ascending order, the LOOKUP function will return the incorrect value.

Applies To

  • Excel for Office 365, Excel 2019, Excel 2016, Excel 2013, Excel 2011 for Mac, Excel 2010, Excel 2007, Excel 2003, Excel XP, Excel 2000

Type of Function

  • Worksheet function (WS)

Example (as Worksheet Function)

Let's look at some Excel LOOKUP function examples and explore how to use the LOOKUP function as a worksheet function in Microsoft Excel:

=LOOKUP("T", {"s","t","u","v";10,11,12,13})
Result: 11

=LOOKUP("Tech on the Net", {"s","t","u","v";10,11,12,13})
Result: 11

=LOOKUP("t", {"s","t","u","v";"a","b","c","d"})
Result: "b"

=LOOKUP("r", {"s","t","u","v";"a","b","c","d"})
Result: #N/A

=LOOKUP(2, {1,2,3,4;511,512,513,514})
Result: 512

Frequently Asked Questions

Question: In Microsoft Excel, I have a table of data in cells A2:D5. I've tried to create a simple LOOKUP to find CB2 in the data, but it always returns 0. What am I doing wrong?

Answer: Using the LOOKUP function can sometimes be a bit tricky so let's look at an example. Below we have a spreadsheet with the data that you described.

Microsoft Excel

In cell F1, we've placed the following formula:

=LOOKUP("CB2",A2:A5,D2:D5)

And yes, even though CB2 exists in the data, the LOOKUP function returns 0.

Now, let's explain what is happening. At first, it looks like the function isn't finding CB2 in the list, but in fact, it is finding something else. Let's fill in the empty cells in D3:D5 to explain better.

Microsoft Excel

If we place the values TEST1, TEST2, TEST3 in cells D3, D4, 5, respectively, we can see that the LOOKUP function is in fact returning the value TEST2. So we ask ourselves, when we are looking up CB2 in the data and CB2 exists in the data, why is it returning the value for CB19? Good question. The LOOKUP function assumes that the data in column A is sorted in ascending order.

If you look closer at column A, it is not in fact sorted in ascending order. If we quickly sorted column A, it would look like this:

Microsoft Excel

Now the LOOKUP function correctly returns 3A when it is looking up CB2 in the data.

To avoid these sorting problems with your data, we recommend using VLOOKUP function in this case. Let's show you how we would do this. If we changed our formula below (but left our data in column A in the original sort order):

Microsoft Excel

The following VLOOKUP formula would return the correct value of 3A.

=VLOOKUP("CB2",$A$2:$D$5,4,FALSE)

The VLOOKUP function does not require us to have the data sorted in ascending order since we used FALSE as the last parameter - which means that it is looking for an exact match.


Question: I have the following LOOKUP formula:

=LOOKUP(C2,{"A","B","C","D","E","F","G","H","I","K","X","Z"}, {"1","2","3","4","5","6","7","8","9","10","12","1"})

I also need to add zero to the lookup vector and result vector. How do I do this?

Answer: Using numbers in Excel can be tricky, as you can enter them either as numeric or text values. Because of this, there are 2 possible solutions.

Numeric Solution

If you have entered your zero as a numeric value, then the following formula will work:

=LOOKUP(C2,{0,"A","B","C","D","E","F","G","H","I","K","X","Z"}, {0,"1","2","3","4","5","6","7","8","9","10","12","1"})

Text Solution

If you have entered your zero as a text value, then the following formula will work:

=LOOKUP(C2,{"0","A","B","C","D","E","F","G","H","I","K","X","Z"}, {"0","1","2","3","4","5","6","7","8","9","10","12","1"})

Question: For the following function in Microsoft Excel:

=LOOKUP(M14,Sheet2!A2:A2240,Sheet2!B2:B2240)

How do I get it to return a blank cell if the LOOKUP value (M14) is blank?

Answer: To check for a blank value in cell M14, you can use the IF function and ISBLANK function as follows:

=IF(ISBLANK(M14),"",LOOKUP(M14,Sheet2!A2:A2240,Sheet2!B2:B2240))

Now if the value in cell M14 is blank, the formula will return a blank. Otherwise it will perform the LOOKUP function as before.