President Donald Trump's new tax law went into effect this year, changing the 2018 tax brackets.

The tax law resulted in a bump in take-home pay for about 90% of Americans, according to the IRS.

The changes hit Americans' paychecks at the beginning of February.

President Donald Trump's new tax law, which changed the 2018 tax brackets, went into effect at the start of this year.

By February, many Americans began to notice a bump in their take-home pay thanks to the new tax law.

The IRS released new guidelines in January, known as tax-withholding tables, that help employers calculate how much in taxes to take out of employees' paychecks, Business Insider's Bob Bryan reported. That amount is paid to the IRS in the employee's name.

At the end of the year, when an employee files their tax return, they either get a refund (if too much was withheld) or pay more (if too little was withheld).

The new withholding amounts hit Americans' paychecks around February 1, resulting in roughly 90% of workers seeing an increase in their take-home pay, according to the IRS.

Career site Zippia provided Business Insider with data breaking down the average salaries for employees in various occupations, as well as how their federal tax bill changed under the new tax law. Business Insider used that data to calculate exactly how paychecks have changed since the new tax law went into effect.

Below, a look at how people in a number of different jobs, from fast-food cooks to pilots to anesthesiologists, have seen their biweekly take-home pay (meaning, 26 paychecks per year) change under tax reform. The calculations are for a single person who does not have children and is not a homeowner.

The new paycheck amounts account only for federal taxes and FICA taxes — the employee's share of social security and medicare taxes. Depending on where you live, state and local income taxes will further reduce your take-home pay — as will health insurance premiums, 401k contributions, and other paycheck deductions you may have.