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Does Obama's 'tax calculator' show what an individual's tax cut would be?

The Statement: On its Web site and in a television commercial, the campaign of Democratic presidential nominee Sen. Barack Obama is featuring a "tax calculator" that the campaign says voters can use to see how much their tax cut would be under Obama's plan.

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The Facts: Obama's tax calculator asks users to input information, ranging from an approximate income range to mortgage balance and number of dependents. If the user qualifies for a tax cut under Obama's plan, the calculator produces a specific dollar estimate for "tax savings" and compares that with any estimated tax change for that user under McCain's plan.

For incomes over $250,000, where there would be a possible increase under Obama's plan, the calculator does not provide dollar estimates and tells the user, "You will probably not get a tax cut under the Obama-Biden plan."

McCain supporters and conservative groups such as Americans for Tax Reform criticize the Obama calculator, saying it fails to spell out how tax hikes in Obama's plan would affect a given individual and excludes corporate taxes in its calculations.

In a question-and-answer section, the Obama Web site says it "calculates only how individuals' income taxes change" and does not deal with proposed changes in corporate tax rates by either Obama or McCain.

Robertson Williams, principal research associate for the nonpartisan Tax Policy Center, said that, while his group has not checked all of the calculator's results and was not involved in creating it, the numbers it produces for individual tax cuts "look reasonable" given that they are for income estimates - not specific amounts - and that not all tax factors are included.

"It generally appears to give accurate estimates of the tax savings under Obama's tax proposals - for those who get tax cuts," Williams said, adding that the calculator avoids pointing out possible tax increases or giving estimated amounts of increases. "That clearly focuses attention on the tax cuts rather than the tax increases. But it does not appear to give incorrect results, given very basic assumptions about other factors influencing tax bills," Williams said.

The Verdict: True, but incomplete. While the Obama tax calculator gives what a nonpartisan authority describes as generally accurate estimates for taxpayers who would qualify for tax cuts under Obama, it does not calculate possible increases for some taxpayers or the effects of corporate tax changes.