When working with logical tests in Excel, there is occasionally the need to test the contents of a cell to establish if it is blank or not, to do this, the ISBLANK function will return a suitable response. The ISBLANK function requires just one argument, value, which is the argument that is tested to establish if it is blank or not. If the argument supplied is blank then the returned value is TRUE, if the argument supplied is not blank then the response is FALSE. In this example, the function is supplied a range of values, including blank and non-blank values and the response is shown below.