How do you estimate your income for long term capital gains?
Do short term capital gains count in this income for long term capital gains?
Do short term capital losses reduce income for long term capital gains?
How do you estimate your income for long term capital gains?
Do short term capital gains count in this income for long term capital gains?
Do short term capital losses reduce income for long term capital gains?
The long-term rates are based on your taxable income. This includes your net capital gain (or allowed capital losses) from both short and long-term positions. First you'll calculate your net capital gain/loss for short-term and long-term separately, then you add them together to see how much they contribute to your taxable income (here losses on one would offset gains on the other).
Since the tax rates are based on taxable income, you'll have to estimate all your other income and adjustments/deductions to know the rate you'll pay.
An example, if you had $50,000 in long-term gain and $5,000 in short-term losses, you'd have $45,000 added to your taxable income. If you were single and that was your only income for the year the standard deduction would bring the amount below the 0% long-term threshold so you'd have no capital gains tax due.
Alternatively, if your taxable income before capital gains had you at the top end of the 12% tax bracket and you had $5,000 in short-term gain and $5,000 in long-term gain you'd pay 22% on the short-term gain and 15% on the long-term (the brackets don't perfectly align between ordinary income and long-term capital gains so this example is not perfect, but the point is that the total taxable income determines the rate).