In 2017, the death tax applies to estates worth at least $5,490,000. Unless your estate is worth nearly 5.5 million dollars, it will not be subject to the death tax.
On average about .2% of estates pay the death tax. Annually, less than 5,000 estates are taxed.
If you die in 2017 and leave behind an estate worth 5.5 million dollars, only the last $10,000 of your estate would be taxed at the 40% death tax rate. For this reason, the Tax Policy Center found that the average estate subject to the tax only pays 17% of the value of the estate in taxes.
In 2017, only about 50 small farms and businesses nationwide will have to pay the death tax.
Here is the page from the IRS that describes the death tax.
To learn more about the death tax read Ten Facts you Should Know about the Federal Estate Tax.