How to Do VLOOKUP and Interpolate in Excel (6 Ways)

Sometimes you may need to look up for a value in a range that doesn’t remain exactly in the range rather than locates between two values, in this case, we need to do VLOOKUP and interpolate in Excel simultaneously.
This article will enlighten you about different ways of doing VLOOKUP and interpolation at a time for having desired values.

VLOOKUP and Interpolate in Excel: 6 Ways

Here, we have the sales records of a product with the product code 1234XD5 for different days, but the serial numbers of days are arranged for every other day. So, to know the sales values between these days, we cannot be dependent only on the VLOOKUP function, but we also need to interpolate them to get the exact value for that day.
The following 6 methods will illustrate the procedures of doing this job using different combinations of functions along with a VBA code.

We have used Microsoft Excel 365 version here, and you can use any other version according to your convenience.

Method-1: Using the IFERROR, VLOOKUP, and AVERAGE Functions to Do VLOOKUP and Interpolate

Here, we will calculate the sales value for Day No. 12 by interpolating between the values of Day No. 11 and Day No. 13. For this purpose, we will use the IFERROR, VLOOKUP, AVERAGE, OFFSET, INDEX, and MATCH functions.

Steps:
➤ Type the following formula in cell F5.

Here, E5 is the look-up value, $C$4:$C$11 is the range of days numbers where we will look up value and $D$4:$D$11 is the range of the sales values.

➤ Press ENTER.
You will get 7,353.00 for day 12 which is the interpolation of the sales values between days 11 and 13.

Method-2: Combination of IF, ISNA, VLOOKUP, AVERAGE, and MINIFS Functions to Do VLOOKUP and Interpolate

For looking up the sales value for Day No. 8 we are going to use the combination of the IF, ISNA, VLOOKUP, AVERAGE, and MINIFS here.

➤ Type the following formula in cell F5.

Here, E5 is the look-up value, $C$4:$C$11 is the range of days numbers where we will look up value and $D$4:$D$11 is the range of the sales values.

After pressing ENTER, you will get the sales value of $5,298.50 for day 8 by looking up the values in the range and interpolating between the sales values of days 7 and 9.

Read More: How to Interpolate Missing Data in Excel

Method-3: Using the Combination of the IF, ISNA, VLOOKUP, AVERAGE, INDEX, and MATCH Functions

In this section, we are going to use the IF, ISNA, VLOOKUP, AVERAGE, INDEX, and MATCH functions for searching up the sales value for the day no 12 and interpolating the values for days 11 and 13.

➤ Type the following formula in cell F5.

Here, E5 is the look-up value, $C$4:$C$11 is the range of days numbers where we will look up value and $D$4:$D$11 is the range of the sales values.

➤ Press ENTER.
Afterward, you will get 7,353.00 for day 12 which is the interpolation of the sales values between days 11 and 13.

Method-4: Do VLOOKUP and Interpolate in Excel Using the FORECAST, OFFSET, and MATCH Functions

Here, we will be using the FORECAST, OFFSET, and MATCH functions to look up the sales value for day no 12 with the help of the interpolation.

➤ Use the following formula in cell F5.

Here, E5 is the look-up value, $C$4:$C$11 is the range of days numbers where we will look up value and $D$4:$D$11 is the range of the sales values.

After pressing ENTER, you will get the sales value of $7,353.50 for day 12 by looking up the values in the range and interpolating between the sales values of days 11 and 13.

Method-5: Using the Combination of INDIRECT, ADDRESS, and MATCH Functions

In this section, we will calculate the sales value for the day no. 8 by using the INDIRECT, ADDRESS, and MATCH functions for doing the interpolation and searching the value in the range.

➤ Apply the following formula in cell F5.

Here, E5 is the look-up value, $C$4:$C$11 is the range of days numbers where we will look up value and $D$4:$D$11 is the range of the sales values.

➤ Press ENTER.
Finally, you will get the sales value of $5,298.50 for day 8 by looking up the values in the range and interpolating between the sales values of days 7 and 9.

Read More: How to Interpolate in Excel Graph

Method-6: Using VBA Code to Do VLOOKUP and Interpolate in Excel

If you are fond of VBA and want to do VLOOKUP and Interpolate in Excel using VBA, then this method will be a handy one for you. In this method, we will use a VBA code for searching a value in a range, and then, get the desired result with the help of the interpolation.

Steps:
➤ Go to the Developer Tab >> Visual Basic Option.

Then, the Visual Basic Editor will open up.
➤ Go to the Insert Tab >> Module Option.

After that, a Module will be created.

➤ Write the following code

Function vlookupforintermediates(day As Variant, dayrange As Variant, _
salesrange As Variant) As Double

Dim j, small_day, large_day As Variant
small_day = WorksheetFunction.Min(dayrange.Value)
large_day = WorksheetFunction.Max(dayrange.Value)
Dim increment, small_increment, large_increment As Integer
small_increment = 0
large_increment = 0
increment = 0

For Each j In dayrange
increment = increment + 1
If j.Value = day Then
vlookupforintermediates = salesrange(j).Value
Exit Function
End If
Next j

increment = 0

For Each j In dayrange
increment = increment + 1
If j.Value < day Then
   If j.Value >= small_day Then
   small_day = j.Value
   small_increment = increment
   End If
End If
If j.Value > day Then
   If j.Value <= large_day Then
   large_day = j.Value
   large_increment = increment
   End If
End If
Next j

vlookupforintermediates = salesrange(small_increment).Value + (day - small_day) * _
(salesrange(large_increment).Value - salesrange(small_increment).Value) _
/ (large_day - small_day)

End Function

Here, we have created a function with the name vlookupforintermediates, and the variables under this function as inputs are day, dayrange, and salesrange all of them are declared as Variant. Moreover, we have declared j, small_day, and large_day as Variant and increment, small_increment, and large_increment as Integer.
Using the MIN and MAX functions small_day and large_day are assigned to the smallest day and largest day.
The first FOR loop will return the sales values for any day which is present in the day’s ranges and the second FOR loop with the IF-Then statement will store value to the small_increment and large_increment variables.
Finally, using the formula for calculating interpolation this function will return our desired value.

After saving the code, you have to return to the main sheet.
➤ Use the following formula in cell F5.

Here, vlookupforintermediates is the created function name, E5 is the day, C4:C11 is the dayrange, and  D4:D11 is the salesrange.

➤ Press ENTER.
Eventually, you will get the sales value of $7,353.00 for the specific day no. 12.

Read More: How to Do Linear Interpolation Excel VBA

Practice Section

For doing practice by yourself, we have provided a Practice section like below in a sheet named Practice. Please do it by yourself.

Download Workbook

Conclusion

In this article, we tried to show the ways to do VLOOKUP and interpolate in Excel easily. Hope you will find it useful. If you have any suggestions or questions, feel free to share them in the comment section.

Related Articles

• How to Do Linear Interpolation in Excel
• How to Do Interpolation with GROWTH & TREND Functions in Excel
• How to Interpolate Between Two Values in Excel
• How to Perform Bilinear Interpolation in Excel
• How to Use Non Linear Interpolation in Excel