工资个税的计算公式为：

应纳税额=（工资薪金所得 －“五险一金”－扣除数）×适用税率－速算扣除数     

扣除标准：个税按3500元/月的起征标准算

我们此处简化五险一金，假设为0，则

如果某人的工资收入为5000元，他应纳个人所得税为：(5000—3500)×3%—0=45(元)。

税率表如下：

代码

public static void main(String[] args) {
        
        Scanner scan = new Scanner(System.in);
        System.out.println("请输入您的工资：");
        
        double salary = scan.nextDouble();
        double deductionAmount = 3500;//扣除数
        double taxSalary = salary-deductionAmount;//应上税的工资
        double taxRate = 0;//税率
        double quickCalculationDeduction = 0;//速算扣除数
        
        if(taxSalary>0) {
            if(taxSalary<1500) {
                taxRate = 0.03;
                quickCalculationDeduction = 0;
            }else if(taxSalary<4500) {
                taxRate = 0.1;
                quickCalculationDeduction = 105;
            }else if(taxSalary<9000) {
                taxRate = 0.2;
                quickCalculationDeduction = 555;
            }else if(taxSalary<35000) {
                taxRate = 0.25;
                quickCalculationDeduction = 1005;
            }else if(taxSalary<55000) {
                taxRate = 0.3;
                quickCalculationDeduction = 2755;
            }else if(taxSalary<80000) {
                taxRate = 0.35;
                quickCalculationDeduction = 5505;
            }else {
                taxRate = 0.45;
                quickCalculationDeduction = 13505;
            }
            
            double taxPayable = taxSalary*taxRate-quickCalculationDeduction;
            System.out.println("当月应缴纳的税额为："+taxPayable);
            
        }else {
            System.out.println("您的工资未到达起征点，请继续努力~");
            
        }
        
    }