The main difference between the salary and hourly calculator is that the salary calculator is paid to an employee on the basis of an annual amount that is known as salary and hourly calculator is based on the hourly payment. This is the basic difference between the salary and hourly calculator. For a salaried employee, the number of hours worked in a month can vary without affecting the total salary fixed. In case of hourly calculated payment, the number of hours worked has a direct impact on the payment received. If the number of hours worked is less then the hourly calculated payment will also be less.