Up to 250000. Nil
250000 to 500000 - 10 % by which amount exceeds Rs 250000, that is in your case Rs 250000 x 10 % is chargeable to tax.
500000 to 1000000 - 20 % by which amount exceeds 500000 , that is in your case 4000 is chargeable to tax 20% tax
Total estimate tax payable is 25800.
Now lets calculate average rate of income tax = Estimated tax 25800 x 100 / Total Income = 504000.00 = 5.119 %
So your monthly deduction rate is 5.119 % , that is 42000 x 5.11 % = 2147/ per month.
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Section 192 TDS on Salary rate and computation - Taxin
Now you can reduce the rate by cutting the estimate tax payable. Income tax allow us various deduction of taxable incomes under various section. Just intimate your employer about any one of the deduction allowed below if you really having it.
Deduction Under Section 80 C - basic deductions.
Deduction under section 80TTA - Interest from savings.
Deduction under section 80G - Donation to charity.
Deduction under section 80D - Medical insurance premium.
Deduction under section 80E - Interest on educational loan.