The tools put you in one of the four categories by asking you multiple-choice questions about yourself and your finances. People rated excellent risks, naturally, get the lowest rate in the range--or one near the bottom; those rated poor risks pay the highest rate or one near the top. If you're fair or good, you're in between.
How many card holders fail to pay off their balance before their teaser rate expires? "A significant percentage," says Woolsey—more than half.
Before the recession, he says, credit card customers could "kick the can down the road" almost indefinitely, transferring their balances from one card's introductory zero-offer to the next. Today, that's not so easy. Yes, credit standards are relaxing. Yes, grace periods are lengthening. But we're still not back to the comparatively lax standards 2007.
If you take a zero rate, advises Woolsey, "You should make hay while the sun shines." Meaning? Pay off your balance before you get dinged with the higher rate.