Is the salary fixed before tax or after tax?

Now the general recruitment is to write the pre-tax salary, which generally includes five insurances and one gold. Calculation method of individual income tax: from 20 11September1,the tax threshold is 3,500 yuan. If your monthly salary is 3500 yuan, you don't have to pay personal income tax. Personal income tax payable = (salary income-four insurances and one gold paid by individuals-personal income tax deducted 3500.