What credit card offers and rewards are best for you?

On the surface, the HSBC Platinum MasterCard with Cash or Fly Rewards and the Capital One Venture card seem comparable. If you like to travel, you might find their pitches enticing: Both let you earn points that you can use for plane tickets. But a cardholder charging $1,500 a month would get $460 worth of points in the first year with the Capital One card and only $180 with HSBC's card.

Whether you'd uncover that difference is debatable. Sure, you're a savvy consumer. But these days, picking the right rewards card—the most heavily marketed type—seems to require an advanced degree in mathematics. Many have complex formulas for determining how much cash or how many points you'll earn. Some cards come in two versions: one with no annual fee and another with a fee but higher rewards.

If you carry a credit-card balance, you'll have to do some calculations to determine whether you'll save by transferring it. Some cards offer a 0 percent annual rate on balance transfers, but only for a limited time and for an up-front fee.

To help you make sense of the wide range of credit-card deals, the Consumer Reports Money Lab developed a computer model for evaluating cards. It takes into account the total costs of carrying and transferring a balance and estimates the rewards you stand to earn based on your spending patterns. We tracked down the terms of 53 mass-market credit cards and used the calculator to determine the best ones for three types of users: families looking for cash rewards, leisure travelers who want free trips, and cardholders who carry a balance. We also gave credit-card makeovers to four readers for whom we found better cards than what's in their wallets.

Here's what else we found:

• Rewards cards offer tempting sign-up deals to consumers with good credit scores. If you haven't compared your cards with what's available now, you should.
• Annual fees might be worth paying for frequent travelers and big spenders.
• Mass-market airline cards are offering perks—travel insurance and free checked baggage, for example—that used to come only with high-fee premium cards.
• Although 0 percent transfer cards seem enticing, especially if you have a big balance to pay off, a low-rate card might be the better deal in the long run.

Up-front bonuses of 25,000 to 40,000 points have become common among travel cards, and occasionally you'll see a juicy 100,000-point offer. Travel cards often charge annual fees, though many are waived for the first year. But the perks that come with many airline cards—expedited security clearance, priority boarding, free checked luggage, and access to airport lounges—can more than make up for the fee. "It's silly not to get an airline card with free checked baggage, because it pays for itself after a single trip," says George Hobica, publisher of the Airfarewatchdog website, which tracks airline deals.

But don't assume that cards offering a 25,000-point sign-up bonus will get you anything more than a one-way ticket. You might need to spend up to 50,000 points for a domestic unrestricted round-trip ticket. "Before you even think about an airline card or other points card, consider what you'd get from a cash-rebate card—it's cash in hand with no restrictions," says Tim Winship, editor of FrequentFlier.com. If you want an airline-specific card because that carrier is the one you usually fly, you might want to wait for a big sign-up offer before you apply.

International travelers can choose from about three dozen travel cards that don't charge foreign-transaction fees (typically 3 percent with cards that do, which would cost you $90 on a $3,000 overseas vacation). And some U.S. issuers, notably Wells Fargo and Bank of America, now offer chip-and-PIN cards, also called EMV smart cards (the acronym comes from Euro­pay MasterCard Visa). Those cards, prevalent in Western Europe, are more secure than the magnetic-stripe type issued in the U.S. If you travel to Europe, it might be worth getting one because standard cards are often not accepted at subways, parking facilities, and gas stations.

If you have a basic cash-back card, rewards should be straightforward. But some cards have formulas that are anything but. Chase Freedom, Citi Dividend, and several Discover cards tout rewards of up to 5 percent, but only on quarterly rotating categories, such as home-­improvement purchases in the spring and hotels in the fall. You have to opt in each quarter to qualify for those rewards. And you have to plan your spending around each category, which can be difficult because sometimes the categories might not be announced well in advance. Spending in some categories, such as gas, might earn the maximum rewards only up to a certain amount, after which the percentage rewards are lower. For instance, from July through September, the Discover More card paid 5 percent on gas, theme parks, and movies, up to $1,500 in total purchases. After that, you'd have earned only 0.25 percent, unless you'd spent $3,000 in nonbonus categories for the year.

That kind of complexity can make it difficult for cardholders to maximize their rewards. Shane Tripcony, 42, of Little Rock, Ark., a father of two and entrepreneur who runs a Web marketing and development company, has two credit cards but is not earning the kind of rewards he could be. He and his wife, Erin, tend to use cash or a debit card for gas and groceries rather than credit, even though they pay off their balances in full and on time each month. He wants to boost his cash-back rewards by charging his children's private-school tuition—almost $15,000 a year.

Though he doesn't travel often, he's considering signing up for the American Express Hilton HHonors card to use for an upcoming family vacation. Tripcony figures the trip's cost would be largely covered by the card's up-front bonuses of 40,000 points after the first $750 in purchases. But how far the bonus points go will depend on the type of hotel and room he books. Hilton ranks its hotels in seven categories. A standard room in the lowest is available for 7,500 points a night, and the highest category costs 50,000 points a night. The Hilton HHonors rewards website has a search function with results that include the points or dollars needed for a night's stay at all of its properties.

Beyond this vacation, Tripcony could earn many cash rewards if he and his wife used a credit card rather than cash or debit for everyday purchases as well as for tuition. A good card for them might be the American Express Blue Cash Preferred card, which pays rewards of 6 percent on spending in supermarkets, 3 percent at gas stations and department stores, and 1 percent on everything else. Based on their spending habits, charging $3,000 monthly on it would result in a cash reward of about $1,040 in the first year because of an up-front bonus and $890 in subsequent years, even after paying the $75 annual fee.

Jordan Leventhal of Cleveland, a 23-year-old college student who works as a paramedic, has accumulated eight credit cards. He has a good credit score and doesn't carry any interest-charging balances. He tries to match up his purchases with the cards that pay the highest rewards for what he's buying. But by spreading his spending among so many cards, he's missing out on opportunities to maximize his rewards.

For instance, he wisely opted in to the summertime offer by the Chase Freedom Visa card that paid 5 percent cash back on gas and restaurants—his two biggest spending categories—and 1 percent on everything else. But he has also used other cards to buy gas and restaurant meals, missing out on getting 5 percent back on those occasions. He also has a United card that he took out to get a free-flight sign-up bonus; he uses it for nontravel purchases but is a long way from earning another reward ticket. Though it has an annual fee, the United card is worth holding to book flights on that airline because it pays 2 miles per dollar spent on flights and provides free baggage checks. But he should concentrate all of his other spending on higher-rewarding cards, such as the Chase Freedom card for purchases that qualify under its 5 percent seasonal promotions and the Capital One Cash rewards card for everything else. That card pays 1 percent on everything and adds a 50 percent bonus on cash back at the end of the year.

Rewards cards aren't suitable for cardholders who carry a balance, because they generally carry higher APRs than other cards. Robert Muthumbi, 41, of Flowery Branch, Ga., owes $5,425 on his Capital One card, which has a 22.9 percent APR, and $5,000 on a Discover card at 16 percent. For several years, he's been in "repayment mode," paying two to three times the minimum balance due each month in an effort to clear it. The issuers have refused to reduce his interest rate.

Muthumbi's best option is to transfer the balances to a card with a lower APR. Many cards offer 0 percent financing for 12 to 18 months, though most charge a transfer fee of 3 or 4 percent up front. After the introductory period ends, the APRs will probably jump to between 12 and 22 percent. So Muthumbi needs to figure out how long it will realistically take to pay off his balances. If he can do it in 15 months, his best bet is the Chase Slate card, which offers 0 percent for that time period and no balance-transfer fee if the transfer is made within 60 days of opening the account.

If it will take more than two years, he should choose the PenFed Promise card, which currently has an APR of 4.99 percent for the life of the balance, with no transfer fee. (To get the card, you need to join the Pentagon Federal Credit Union. Membership is free for members of the military and their families, federal employees, and members of qualifying organizations. Others can join by making a $15 donation to a military-family nonprofit. Go to penfed.org for details.) Other cards that have low transfer APRs include some from Simmons and IberiaBank.

Once Muthumbi finds a good balance-transfer card, he should make his everyday purchases with another card that gets paid off each month. His new card might have a different APR for purchases and balance transfers, which could cause him to compound his debt.

Dana Kippel, 23, of Delray Beach, Fla., has been rejected for several credit cards, including those from Macy's and Nordstrom. She was also turned down for a card by Chase, where she maintains a bank account. She works full-time but hasn't built a credit history. She wants a credit card so that she can begin doing that.

Cards aimed at people with little or limited credit history often have huge startup costs, monthly maintenance fees, and giant interest rates. We found real lemons, such as several cards from First Premier Bank that charge $170 in first-year fees. The Matrix Card by Discover from Continental Finance had high ongoing costs. In the second year, a $12 monthly fee kicks in on top of a $75 annual fee, for total charges of $219 a year. Its 29.99 percent APR is also among the higher ones we've seen, though the 36 percent APR charged by several First Premier cards eclipsed that rate.

Kippel would be smart to avoid such cards. Because she has already been turned down by Chase and several retailers, her best option is a secured card, which requires a security deposit that is generally equal to your spending limit. The Capital One Secured MasterCard reports to all three major credit bureaus. It has an annual fee of $29 and its APR is currently 22.9 percent, but it has a low maximum late-payment fee of up to $19. Kippel can get an initial credit limit of $200 by putting down a refundable deposit of as little as $49, depending on her creditworthiness. After she establishes a good payment history over 12 to 18 months, she can ask Capital One or another bank for a standard credit card.

Consumers Union, the advocacy arm of Consumer Reports, supported reform that led to the so-called Schumer Box (a required summary of the costs of a credit card in promotional materials, named after Sen. Charles Schumer, D-N.Y., who as a congressman championed the legislation) and the passage of the Card Act of 2009, which outlawed certain abusive practices by issuers. But today's confusing card deals suggest that issuers need to make their deals more understandable to typical consumers—not just for those with math degrees.

Until then, be sure to read all of the fine print on any offer you're considering. Here's what to watch for:

Spending tiers. Some rewards cards require you to spend a certain amount to get the advertised perks. Watch for phrases such as "up to" in card offers—that may mean you'll get the highest rewards only after spending thousands in a single year.

Hidden caps. Some cards, including some gas cards, reduce the reward percentage after you've spent a set amount.

Expiration dates. Check for them on rewards, especially with travel cards, because it often takes a long time to get enough points for a ticket.

Missed-payment penalties. Some cards take away your month's rewards if you miss a payment, and they might charge a fee to reinstate them. The Discover More card, for example, takes away all of your points if you miss two payments in a row.

Changes in terms. Avoid surprises by reading the notices that come with your monthly bills for changes in fees, rates, credit limit, or rewards programs.

If your credit-card issuer isn't solving your problem—a billing dispute, say, or trouble closing your account—submit a complaint to the Consumer Financial Protection Bureau. The agency gives issuers 60 days to resolve and close most complaints before it takes further enforcement action.

The Consumer Reports Money Lab analyzed 53 mass-market credit cards to see which ones make the most sense for typical creditworthy users with varying needs. Cards are listed in order of best rewards or lowest cost for the first year.

Calculations are for comparative purposes only and assume a high-credit-score individual. Your actual rewards and costs may vary. Excludes cards not available to the general public, airline-affiliated cards, those requiring enrollment in quarterly bonus categories for highest rewards, points cards that don't convert points to cash or cash equivalents, and travel cards that don't allow bookings on multiple airlines. Data current as of August 2012.

*Rewards take into account up-front bonuses as well as annual fees.

**Cumulative cost estimates assume the balance remains constant at $10,000 over the different time periods and uses the same billing profile across all cards.

***Membership in Pentagon Federal Credit Union required.