What will be my take home salary in Chicago if I file as married jointly and I have no children. I am the only income earner. What is the effective tax rate and how much federal/state allowances do I claim?
To calculate your allowances for the US Federal tax, you can use the worksheet attached to the form W-4.
Similar form (with a similar worksheet) is available for state taxes, on the Illinois Department of Revenue web site.
There are online tax prep sites, H&R Block among them. You'll be able to enter your projected details, and do a 'what-if' type scenario by adding things that impact the return. You don't mention any Schedule A deductions. No mortgage? Planning to have money taken off the top to a 401(k)?