Maximum taxes

"Refund is not important: not owing is"...you are speaking my language!

When your tax situation is simple: single, one job, no dependents, no exemptions, then your employer's payroll calculations should get you pretty close to an "even-dollar" return -- one in which you don't owe money, but you don't get a refund either. The "default" answers for the W-4 reflect your situation that you've described in your question, so you shouldn't need to make any calculations or add any additional information.

Be aware, though, of sneaky "extra" income that could cause you to owe taxes. If you have interest income, or earn money by working at the polls, or have investment income -- there is probably not any withholding taking place on that income.

Or -- if your taxable income is over $100k (meaning that you are in or close to the 24% tax bracket), then a bonus at work could also mean that you may owe at the end of the year. (Many employers withhold taxes from bonus payments at 22% -- regardless of what is on your W-4.)

If your tax situation is truly very straightforward, the default W-4 payroll calculations will get you close to that even-dollar return. If you want to check the impact of any of the "extra" things that might happen throughout the year, you can get your most recent paycheck and use the TurboTax W-4 Calculator or the IRS Tax Withholding Estimator to double-check your expected end-of-year results.