The 2023 Tennis Open Karlsruhe was a professional tennis tournament played on clay courts. It was the first edition of the tournament which was part of the 2023 ATP Challenger Tour. It took place in Karlsruhe, Germany between 3 and 9 July 2023.
Singles main-draw entrants
Seeds
1 Rankings are as of 26 June 2023.
Other entrants
The following players received wildcards into the singles main draw: Liam Gavrielides Henri Squire Marko Topo
The following players received entry from the qualifying draw: Dali Blanch Hady Habib Tim Handel Oriol Roca Batalla Akira Santillan Denis Yevseyev
Champions
Singles
Alejandro Tabilo def. Giulio Zeppieri 2–6, 1–0 ret.
Doubles
Neil Oberleitner / Tim Sandkaulen def. Vít Kopřiva / Michail Pervolarakis 6–1, 6–1.