| Challenger Bangkok | 01/14 09:10 | 25 | [298] Mirza Basic v Daniel Altmaier [260] | 7-6,7-5 | |
| Challenger Ann Arbor | 01/11 20:45 | 28 | [276] Daniel Altmaier v Ulises Blanch [419] | 3-6,4-6 | |
| Challenger Ann Arbor | 01/10 21:35 | 27 | [276] Daniel Altmaier v Edan Leshem [385] | 7-6,7-5 | |
| Challenger Ann Arbor | 01/09 23:45 | 26 | Aleksandar Kovacevic v Daniel Altmaier | 7-5,6-7,3-6 | |
| Challenger Ann Arbor | 01/08 15:00 | 25 | [416] Alen Avidzba v Daniel Altmaier [276] | 4-6,7-6,3-6 | |
| ITF M15 Santo Domingo | 12/01 14:00 | 29 | [277] Jan Choinski v Daniel Altmaier [321] | 3-6,6-4,4-6 | |
| ITF M15 Santo Domingo | 11/30 13:55 | 28 | Nick Hardt v Daniel Altmaier | 3-6,4-6 | |
| ITF M15 Santo Domingo | 11/29 14:00 | 27 | Ricardo Rodriguez v Daniel Altmaier | 4-6,2-6 | |
| ITF M15 Santo Domingo | 11/28 16:35 | 26 | Daniel Rodrigues v Daniel Altmaier | 4-6,3-6 | |
| ITF M15 Santo Domingo | 11/27 18:35 | 25 | Simon Yitbarek v Daniel Altmaier | 5-7,0-6 | |
| ITF M15 East Lansing | 11/24 16:55 | 29 | [356] Michael Geerts v Daniel Altmaier [319] | 6-4,3-6,0-6 | |
| ITF M15 East Lansing | 11/23 21:45 | 28 | [445] Lucas Gerch v Daniel Altmaier [319] | 1-6,6-7 | |
| ITF M15 East Lansing | 11/22 19:05 | 27 | Kyle Seelig v Daniel Altmaier | 4-6,4-6 | |
| ITF M15 East Lansing | 11/21 17:00 | 26 | Alex Kobelt v Daniel Altmaier | 2-6,4-6 | |
| ITF M15 East Lansing | 11/20 15:00 | 25 | Jody Maginley v Daniel Altmaier | 1-6,1-6 | |
| Challenger Champaign | 11/13 16:00 | 25 | [255] Jeffrey John Wolf v Daniel Altmaier [365] | 6-2,7-6 | |
| Challenger Champaign | 11/12 18:10 | 24 | [468] Wilson Leite v Daniel Altmaier [365] | 0-6,5-7 | |
| ITF M25 Malibu | 11/10 20:00 | 29 | Alexander Sarkissian v Daniel Altmaier | 2-6,4-6 | |
| ITF M25 Malibu | 11/09 22:40 | 28 | [395] Collin Altamirano v Daniel Altmaier [364] | 6-7,6-2,5-7 | |
| ITF M25 Malibu | 11/08 19:50 | 27 | Brandon Holt v Daniel Altmaier | 6-7,2-6 | |
| ITF M25 Malibu | 11/07 21:45 | 26 | Enrique L Rico v Daniel Altmaier | 2-6,6-4,2-6 | |
| ITF M25 Malibu | 11/06 20:10 | 25 | Joshua Ortlip v Daniel Altmaier | 3-6,3-6 | |
| Challenger Hamburg | 10/25 15:10 | 27 | [403] Daniel Altmaier v Elias Ymer [130] | 6-4,3-6,6-7 | |
| Challenger Hamburg | 10/24 13:55 | 26 | [368] Jelle Sels v Daniel Altmaier [403] | 4-6,6-7 | |
| Challenger Hamburg | 10/23 15:25 | 25 | [403] Daniel Altmaier v Filippo Baldi [212] | 6-2,6-4 | |
| Challenger Hamburg | 10/22 11:15 | 24 | Vadym Ursu v Daniel Altmaier | 1-6,5-7 | |
| Challenger Hamburg | 10/22 08:00 | 24 | Julian Lenz v Daniel Altmaier | Cancelled | |
| Challenger Ismaning | 10/16 11:35 | 25 | [410] Daniel Altmaier v Constant Lestienne [224] | 3-6,5-7 | |
| Challenger Ismaning | 10/15 09:30 | 24 | [410] Daniel Altmaier v Jan Choinski [297] | 4-6,6-4,7-6 | |
| ITF M15 Bad Salzdetfurth | 10/10 11:10 | 26 | Stefan Seifert v Daniel Altmaier | 6-4,7-5 |
Wikipedia - Daniel Altmaier
Daniel Altmaier (German pronunciation: [ˈdaːni̯eːl ˈaltmaɪ̯ɐ]; born 12 September 1998) is a German professional tennis player. He has a career high ATP singles ranking of world No. 47, achieved on 2 October 2023. He is the current German No. 3.