If you get paid once per month, that's easy -- just look on your pay stub for the after-deductions total.

If the amount fluctuates month to month because of different deductions, ask your employer to provide you with the amount of your total pay for the year after all deductions, and divide that number by 12.

If don't get paid monthly, you'll need to do some math. Determine your pay after deductions, and then use the following chart to help figure out what your monthly take-home pay is:

• For weekly cheques, multiply by 4.333
• For every-two-week cheques, multiply by 2.167
• For twice-a-month cheques, multiply by 2
• For irregular annual income, divide the net total by 12

You also want to make sure you add in other sources of income, such as interest income, spousal support, child support, rent, and other payments. As with your paycheques, determine a monthly average for these streams.