It depends on your filing status and your tax income.
For an example, for the year 2008, if you are filing your tax return as a single taxpayer, if your taxable income
$0 to 8,025 - you pay 10%
$8,025 to 32,550 - you pay 15% plus $802.50
$32,550 - to $78,850 - 25% plus $4,481.25
Let's just say for example that your taxable income (without this sale) was $25,000. Using the chart above, you can see that you still have a "float" of $7,550 before you would go to the next tax bracket which is 25%. That means that $7,550 of any capital gain would qualify to be taxed at zero percent. Any capital gain over that amount is taxed at 15%.
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