Youngest Players at Year-End No. 1
| Rank | Player | Age at EOY No. 1 | Year |
|---|---|---|---|
| 1 |  Carlos Alcaraz | 19y 7m 21d | 2022 |
| 2 |  Lleyton Hewitt | 20y 10m 7d | 2001 |
| 3 |  Andy Roddick | 21y 3m 29d | 2003 |
| 4 | Jimmy Connors | 22y 3m 28d | 1974 |
| 5 | Jim Courier | 22y 4m 11d | 1992 |
| 6 | Pete Sampras | 22y 4m 15d | 1993 |
| 7 | Rafael Nadal | 22y 6m 26d | 2008 |
| 8 | John McEnroe | 22y 10m 12d | 1981 |
| 9 |  Guillermo Vilas | 23y 4m 12d | 1975 |
| 10 |  Jannik Sinner | 23y 4m 14d | 2024 |
| 11 |  Roger Federer | 23y 4m 19d | 2004 |
| 12 |  Bjorn Borg | 23y 6m 25d | 1979 |
| 13 |  Gustavo Kuerten | 24y 3m 15d | 2000 |
| 14 | Mats Wilander | 24y 4m 4d | 1988 |
| 15 |  Novak Djokovic | 24y 7m 4d | 2011 |
| 16 | Stefan Edberg | 24y 11m 12d | 1990 |
| 17 | Ivan Lendl | 25y 9m 23d | 1985 |
| 18 |  Ilie Nastase | 27y 5m 12d | 1973 |
| 19 |  Andy Murray | 29y 7m 11d | 2016 |
| 20 | Andre Agassi | 29y 7m 28d | 1999 |