Starting in tax year 2018, personal exemption deductions for yourself, your spouse, or your dependents were eliminated.
Refer to IRS Publication 501 Dependents, Standard Deduction, and Filing Information and Dependents - Rules for Claiming for additional information about exemptions and whom you may claim as a dependent. You may also wish to utilize the IRS Interactive Tax Assistant (ITA) Whom May I Claim as a Dependent? topic.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.