The Unified Estate Tax Credit will increase to an amount that equates to $5,600,000 for 2018 per individual. So basically, if you are married, as a couple, you can leave $11,200,000 estate tax free. (Speak with an attorney to know the nuances of effectively obtaining the benefits for both spouses; ask about portability.)
Relatedly, you can give away $15,000 per year per donee in 2018. For gift tax purposes, you can gift-split as well, so you and your spouse can give $30,000 per year per donee after January 1. These annual exclusions are over and above the lifetime unified credits.
Forbes has a good explainer for further detail.
UPDATE: Congress has passed a tax bill which fundamentally alters the above referenced numbers. The president is expected to sign.
However, do not confuse or conflate these estate and gift tax exemptions with Medicaid rules. Medicaid counts all gifts; there are no amount of transfers of assets for less than fair market value which are exempt. These federal estate and gift tax exclusions do not apply when calculating Medicaid eligibility.
