It's useful to do a quick back-of-the-envelope calculation. Take your taxable wages, subtract the standard deduction, and then multiply that by the percentage in your bracket. For example, if you were single and made $50,000, you'd subtract $12,000 from that, leaving you $38,000, putting you in the 12% tax bracket. Multiply $38,000 by 0.12 and you get $4560. Compare this to the total amount of taxes you've paid for the year and you'll get roughly what you'll owe or be owed by the federal government. This is just a ballpark figure, especially if you plan to itemize your deductions, but it'll give you a baseline to spot any egregious errors. And if you're dreading the results, uncertainty will only amp up your anxiety and make you more likely to put it off, so it can help settle your mind, for better or worse.