CHAR and VARCHAR are both ASCII character data types by default. But they have the following major differences:

► CHAR stores values in fixed lengths. Values are padded with space characters to match the specified length.

► VARCHAR stores values in variable lengths. Values are not padded with any characters. But 1 or 2 extra bytes are added to store the length of the data.

The table below shows you a good comparison of CHAR and VARCHAR data types:

Value CHAR(4)  Length 

''  ' '  4 bytes

'ab'  'ab '  4 bytes

'abcd' 'abcd'  4 bytes 

Value VARCHAR(4) Length

''  ''  1 byte 

'ab'  'ab'  3 bytes

'abcd' 'abcd'  5 bytes