The IRS says 9 out of 10 filers who efile and choose direct deposit will get their refunds within 21 days. Some returns are processed fairly quickly, while others require additional processing due to specific items in the return. Some are pulled at random for more thorough investigation.

If you efiled, double-check to be sure the return was efiled successfully and accepted.
Sign into your Online Account and check the efile status at the Tax Home.

If that showed it was accepted, you can use the tool at the IRS website below to monitor the status of your Federal refund.   NOTE: You have to wait at least 24 hours after being accepted before using the tool.
https://www.irs.gov/Refunds

NOTE: When using that tool, use only the Federal refund amount, and not any total refund amount that includes a state refund.
The amount to use is on your Federal Form 1040, Line 21a.

NOTE: By law, the IRS will not begin issuing refunds on tax returns claiming the Earned Income Tax Credit or Additional Child Tax Credit until after February 15. So filers with those credits likely won't get their refunds until late February, or in some cases, early March.

To track a state refund:
https://ttlc.intuit.com/community/refund-status/help/how-do-i-track-my-state-refund/00/25571