There are a few software programs that will import your trade data and figure it all out.  Read the FAQ at one of the sites here.  It's very informative.  https://bitcoin.tax/faq  Also, the IRS tax guide here:  https://ww w.irs.gov/pub/irs-drop/n-14-21.pdf - broke the link on purpose.  Knowing the amount I'll have to pay makes me sick.  I know I'll be reported otherwise.