How do you say oh yeah in japense?

In Japanese, "oh yeah" can be expressed as "ああ、そうだ" (ā, sō da) or simply "そうだ" (sō da) to convey agreement or realization. Another casual expression might be "そうだね" (sō da ne), which adds a sense of camaraderie. The choice of expression can vary based on context and formality.