Retirement tax questions

Does taxable compensation appear on any line on Form 1040? I see total income (line 9), AGI (line 11), and taxable income (line 15). Is the calculation total income minus lines 2 through 7?

 

My total income will be close to my total retirement plan contributions this year, so it would be nice if I could calculate an exact number the IRS will be using. 

 

I know how to calculate self-employment income to figure my maximum self-employed retirement plan contributions, if that helps any.