77% of Americans failed this short quiz on tax law changes—here are the 4 questions that stumped them

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It's tax time again, and many Americans are unclear as to how tax reform could affect them.

The Tax Cuts and Jobs Act, which passed in December 2017, made sweeping changes, and many taxpayers could stand to brush up on the details. One study found that 28 percent don't understand exactly what the law changed, while 48 percent say they don't even know what tax bracket they're now in.

Financial website GOBankingRates created a four-question quiz that covers key portions of the law to find exactly what's tripping up Americans, and 77 percent of the 501 respondents failed. "A passing grade means getting more than half the questions right," the site notes.

"Most Americans are in need of a refresher prior to filing their taxes," GOBankingRates concludes. "These results appear to indicate that many taxpayers are poorly informed."

Below are the questions, as well as the correct answers, and the share of respondents who got each right:

1. How much is the standard deduction for a single filer in 2019?

The answer: $12,000
Percentage of respondents who answered correctly: 17.8

A tax deduction is a specific amount of money the Internal Revenue Service allows you to subtract from your total income before taxes are calculated.

You can choose the standard deduction, a flat amount set by the IRS each year, which is "adjusted for inflation and varies according to your filing status," the agency notes. You can also choose to itemize, or individualize, your deductions, which can reduce your taxable income based on certain allowable expenses or disaster losses you may have suffered during the year.

The standard deduction is now $12,000 for single filers. Last year, it was $6,350.

A 2018 IRS report noted that "most taxpayers claim the standard deduction," but each option has its pros and cons, depending on your situation. Here's how to choose which is best for you.

Here's what happens if you don't pay your taxes

2. How much is the penalty for not having health insurance in 2019?

The answer: $0
Percentage of respondents who answered correctly: 51.7

This was the only question that the majority of respondents got right, with more than half "correctly noting that the repeal of the 'individual mandate' — the tax penalty for not having health insurance — is one of the new tax law changes," says GOBankingRates.

In previous years, you could owe a fee if you, your spouse or your dependents were supposed to but didn't have qualifying health coverage.

Keep in mind, that though the new law eliminates these types of penalties moving forward, when you file this year, you could still be on the hook for any lingering 2017 amount and inflation adjustment to be determined.

3. How many different tax brackets are there for tax filers in 2019?

The answer: 7
Percentage of respondents who answered correctly: 10

Tax reform brought changes to the seven tax brackets, which determine the rate you pay on portions of your income. Congress  adjusted the rates and income levels that correspond to each.

NerdWallet: Tax brackets and rates for single filers — click to enlarge

When taxpayers filed returns in 2018, the brackets were 10 percent, 15 percent, 25 percent, 28 percent, 33 percent, 35 percent and 39.6 percent. The brackets that apply this year are 10 percent, 12 percent, 22 percent, 24 percent, 32 percent, 35 percent and 37 percent.

These rules apply only to federal income taxes, NerdWallet notes in its 2018 Tax Study: "Your state might have different brackets, a flat income tax or no income tax at all."

4. What is the tax rate for the highest tax bracket in 2019?

The answer: 37 percent
Percentage of respondents who answered correctly: 12.8

The rate for the highest tax bracket dropped from 39.6 percent to 37 percent.

While, overall, Americans got low scores on the quiz, older millennials seemed "more in tune with the changes included in the new bill," says GOBankingRates. Respondents aged 25 to 34 had the highest passing rate at 27 percent. Those aged 55 to 64 had the lowest passing rate: 16 percent.

"It could just be a sign of the times" that Americans don't know more about their taxes, says GOBankingRates.

Still, it's useful and important to stay informed: Some filers could see lower refunds because of changes to the tax law. And about 30 million could actually owe money to the IRS.

"Staying in the dark about tax law basics will set you up for a potentially rude surprise when you file," GOBankingRates writes, or it might cause you to "plan around a refund that doesn't materialize."

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