The current term for a copyright created today is the life of the author + 70 years.
The date a work is published often determines its copyright term. Here is a basic timeline for published works:
| Before 1924 | In the public domain due to copyright expiration. |
| 1924 to 1977 |
If published without notice: in public domain. If published with notice but copyright was not renewed: in public domain. If published with notice and copyright was renewed: 95 years after publication date. |
| 1978 to March 1, 1989 |
If published without notice: in public domain. If published with notice: no renewal required, term is either 70 years after death of author or December 31 2017 whichever is longer. |
| March 1, 1989 to 2002 |
Notice of copyright no longer required. 70 years after death of author. If it was created before 1978 and first published in this period, term is either 70 years after death of author or December 31 2017 whichever is longer. |
| 2003 to Present | Notice not required. 70 years after death of author. |
Unpublished works: copyright term is life of the author + 70 years or if author/death date is unknown, copyright term is 120 years.
This is a basic timeline, please see Cornell University's Copyright Term and the Public Domain in the United States for a more in-depth chart for determining copyright term.
"Master Flowchart for Evaluating the Copyright Status of a Work Created in the United States Between January 1, 1923 and December 31,1977" in Is it in the Public Domain? by Mannapperuma et al., Berkeley Law, licensed under CC BY-ND.