Beginning in 2000, the Summer Sonic Music Festival is held simultaneously in Tokyo and Osaka over two days in late August and the middle of the summer heat. It attracts a huge array of top international artists—2017 saw Calvin Harris, Foo Fighters, Black Eyed Peas scheduled for the Tokyo and Osaka.
For Tokyo, events will be held at ZOZO Marine Stadium and the adjacent Makuhari Messe. Ticket prices are ¥16,000 for a standard day ticket or ¥30,000 for a “platinum ticket” which gets you welcome drinks, access to an exclusive viewing area, cloakrooms, etc. (see here for details). A standard 2-day pass is ¥29,000. There is also a Sonic Mania event on the Friday before, but separate tickets are required for this (starting at ¥12,000). See the Sonic Mania website for details.