How the VLOOKUP Function Works

Excel's VLOOKUP function, which stands for vertical lookup, can be used to look up specific information located in a table of data or database.

VLOOKUP normally returns a single field of data as its output. How it does this is:

you provide a name or lookup _value that tells VLOOKUP in which row or record of the data table to look for the desired data.

you supply the column number - known as the col_index_num - of the data you seek.

The function looks for the lookup _value in the first column of the data table.

VLOOKUP then locates and returns the information you seek from another field of the same record using the supplied column number.

A function's syntax refers to the layout of the function and includes the function's name, brackets, and arguments.

The syntax for the VLOOKUP function is:

= VLOOKUP ( lookup_value , table_array , col_index_num , range_lookup )

lookup _value (required):
The value you want to find in the first column of the table_array.

table_array - (required):
This is the table of data that VLOOKUP searches to find the information you are after.
The table_array must contain at least two columns of data.
The first column normally contains the lookup_value.

col_index_num - (required):
The column number of the value you want found.
The numbering begins with the search_key column as column 1.
If index is set to a number greater than the number of columns selected in the range argument a #REF! error is returned by the function.

range_lookup - (optional):
It indicates whether or not the range is sorted in ascending order. The data in the first column is used as the sort key.

A Boolean value :
TRUE or FALSE are the only acceptable values.
If omitted, the value is set to TRUE by default.
If set to TRUE or omitted and an exact match for the lookup _value is not found, the nearest match that is smaller in size or value is used as the search_key.
If set to TRUE or omitted and the first column of the range is not sorted in ascending order, an incorrect result might occur. If set to FALSE, VLOOKUP only accepts an exact match for the lookup _value. If there are multiple matching values, the first matching value is returned If set to FALSE, and no matching value for the search_key is found a #N/A error is returned by the function.