Spoiler
It was between chapter 812 and 814 in the manga and in the anime either in chapter 690 or 691.
Subaru (Akai) realises that Conan is indeed Shinichi but they never really talk about it and Conan never really confirms him that.
And
In between 948 and 950 (Manga and 861-862 Anime) Subaru and Conan end up talking about Subaru’s father and when Conan wants to get more information about him Subaru tells him that he will only talk about his familiy once he opens up to him. This implies that he’s pretty sure about Conan being Shinichi.
Sry for my English it’s not my first language.
Hope this helps you
Time for reread ヾ(☆▽☆) Thanks! (づ￣ ³￣)づ
It was such a long time ago and I read much mangas that I completly forgot it. Thank you!
When did akai realize that Conan is shinichi?... or does he not actually know that yet? Cuz the statement in ch1045 was suspicious