I was served an IRS levy yesterday for $6,331. I was told to submit my exemptions, which will aid the IRS in determining the monthly deduction. Now the question I have is, is the amount they deduct based on my gross or net income?

on your net income called disposable pay which for an IRS levy is equal to:Gross Pay without cash tips less taxesless child support orders other less deductions in effect at the time the levy is received. however, a portion of disposable pay is exempt from levy based on your standard deduction, personal exemptions and pay frequency.