Claim 0
If you're someone who prefers to get a larger tax refund, claiming zero is better for you. When you claim zero, you increase the amount of withholding from each paycheck so at the end of the year, you'll have paid in more than you owe (assuming you don't have other income) and you'll get the excess back as a tax refund.Claim 1
When you claim "1" on your W-4, you reduce the amount of income taxes withheld from your paycheck. This means you get more money each paycheck rather than waiting for your tax refund at the end of the year.
