American Masters 12 hr. Outdoor Track & Field Records
| pending | |
| women-only |
Men
| Division | Performance | Name | Location | Date |
| 40-44 | 154,000 m | Bernd Heinrich (44) | Ottawa, CAN | 1984-May-19 |
| 45-49 | 132,000 m | Joe Fejes (47) | Phoenix, AZ | 2012-Dec-15 |
| 50-54 | 140,400 m | Jay Aldous (50) | Phoenix, AZ | 2011-Dec-18 |
| 55-59 | 131,129 m | Gard Leighton (57) | Hayward, CA | 1991-Aug-03 |
| 60-64 | 111,200 m | David Lygre (60) | Queen Creek, AZ | 2002-Dec-31 |
| 65-69 | 120,400 m | Ray Piva (65) | Hayward, CA | 1991-Aug-03 |
| 70-74 | 104,136 m | Gene Dykes (70) | Sharon Hill, PA | 2018-May-12 |
| 75-79 | 94,400 m | Ray Piva (77) | San Diego, CA | 2003-Nov-08 |
| 80-84 | 70,800 m | Bill Dodson (81) | Riverbank, CA | 2016-Mar-18 |
| 80-84 | 72,245 m (p) | Manuel Loverde (84) | Auburn, CA | 2019-Jan-12 |
| 85-89 | 56,648 m | Fred McWald (86) | Riverbank, CA | 2016-Mar-18 |
Women
| Division | Performance | Name | Location | Date |
| 40-44 | 142,000 m | Pam Smith (41) | Sharon Hill, PA | 2016-May-14 |
| 45-49 | 124,300 m | Suzanna Bon (47) | Phoenix, AZ | 2011-Dec-18 |
| 45-49 | 125,391 m (p) | Suzi Swinehart (46) | Phoenix, AZ | 2018-Dec-09 |
| 50-54 | 123,308 m | Connie Gardner (50) | Phoenix, AZ | 2013-Dec-14 |
| 55-59 | 116,227 m | Debra Horn (55) | Phoenix, AZ | 2014-Dec-14 |
| 55-59 | 118,294 m (p) | Connie Gardner (55) | Phoenix, AZ | 2018-Dec-09 |
| 60-64 | 95,604 m | Betty Frankum (62) | San Diego, CA | 2001-Nov-10 |
| 65-69 | 97,530 m | Maria Shields (66) | Sharon Hill, PA | 2017-May-15 |
| 65-69 | 100,175 m (p) | Maria Shields (68) | Sharon Hill, PA | 2019-May-12 |
| 70-74 | 52,303 m | Barbara Ella (71) | Riverbank, CA | 2016-Mar-18 |