This isn’t correct. The calculation can be found as the worksheet on page 33 of https://www.irs.gov/pub/irs-pdf/i1040gi.pdf https://www.irs.gov/pub/irs-pdf/i10

This isn’t correct. The calculation can be found as the worksheet on page 33 of https://www.irs.gov/pub/irs-pdf/i1040gi.pdf https://www.irs.gov/pub/irs-pdf/i1040gi.pdf — regular income gets taxed first, and then long-term gains after. The 15% bracket only applies to the portion in excessof $40k, not the whole amount (lines 11-20 on the worksheet).