'Gross' means before deducting tax or before deducting tax relief.
'Net' means after deducting tax or after deducting tax relief.
Your income tax bill may be reduced if you are married or in a civil partnership and you or your husband, wife or civil partner were born before 6 April 1935.
This calculator does not deal with income (called chargeable gains) from life insurance.
Your National Insurance may be reduced if you are contracted out of the state second pension.
National Insurance is not payable beyond state pension age which is assumed here to be 65 (even though it is, in fact, currently a few years lower for women).