For 2017, Depending on your Tax bracket, it could range from a tax rate of 10 % to 39.6 %. If you sold a Bitcoin after 1 year of owning Bitcoin and convert into USD , is taxed as a Long Term Gain and Taxable rates on those gains range from 0 to 20 percent. and people who sell before one year holding of a Bitcoin, means doing day or weekly trading..treating like they have 1099 Form Income and it could range from a tax rate of 10 % to 39.6 %. Basically it depends on your income. IRS treat with higher-income households, paying the highest rate of tax.
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From @taxgiant