You can only file exempt under special circumstances. Not sure what they all are. It's better to claim more allowances than you need to have less taken out. If you make over 12,000 (the Standard Deduction for Single) you will owe tax on the amount over 12,000. The IRS wants you to pay the tax in evenly during the year and not all at once on your tax return. If you don't you may owe a penalty if you owe too much.
