Summer Wars (2009)
Kernel Score: 85% · 1,007 ratings · Rated PG
Genres: Animation, Science Fiction
Released: 2009-08-01
Runtime: 114 minutes
Where to watch Summer Wars
- Stream: HBO Max
- Rent: Prime Video, Apple TV, Google Play, YouTube
- Buy: Prime Video, Apple TV, Google Play, YouTube
US availability, updated 2026-10-23.
Overview
Teenage math whiz Kenji Koiso agrees to take a summer job at the Nagano hometown of his crush, Natsuki. When he arrives, he finds that her family have reunited to celebrate the 90th birthday of their matriarch. His job: pretend to be Natsuki's fiancé. Meanwhile, his attempt to solve a mathematical equation causes a parallel world's collision with Earth.
Summer Wars parents' guide: ages 8+
Parents need to know that Summer Wars is a PG-rated Japanese animated sci-fi film about a virtual world hacking crisis, family togetherness, and teen romance, suitable for most families.
- Violence & scariness: Some — Includes cyberattack peril and a virtual-world crisis, but violence is largely non-graphic and tech-focused.
Fresh Kernels AI-assessed from the official PG rating, publicly documented content. A guide for families, not an official rating.
Movies like Summer Wars
If you liked Summer Wars, these are the movies we'd watch next.
- The Animatrix (2003) — 80%
- The Mitchells vs. the Machines (2021) — 88%
- Ghost in the Shell: Stand Alone Complex - Solid State Society (2007) — 83%
- Detective Conan: The Phantom of Baker Street (2002) — 87%
- Hello World (2019) — 82%
- Scooby-Doo and the Cyber Chase (2001) — 82%
- Ghost in the Shell 2.0 (2008) — 83%
- Yu-Gi-Oh!: The Dark Side of Dimensions (2016) — 84%
Director
Cast
- Ryunosuke Kamiki as Kenji Koiso (voice)
- Hitomi Miyauchi as Natsuki Shinohara (voice)
- Mitsuki Tanimura as Kazuma Ikezawa (voice)
- Sumiko Fuji as Sakae Jinnouchi (voice)
- Ayumu Saito as Wabisuke Jinnouchi (voice)
- Takahiro Yokokawa as Takashi Sakuma (voice)
- Kiyomi Tanigawa as Yukiko Shinohara (voice)
- Mutsumi Sasaki as Kazuo Shinohara (voice)
- Mieko Nobusawa as Mariko Jinnouchi (voice)
- Takuya Kirimoto as Riichi Jinnouchi (voice)
Summer Wars FAQ
Is Summer Wars good?
Summer Wars has an 85% Kernel Score on Fresh Kernels from 1,007 audience ratings.
Where can I watch Summer Wars?
In the US you can stream Summer Wars on HBO Max and rent it from Prime Video, Apple TV, Google Play and YouTube.
Is Summer Wars OK for kids?
Summer Wars is rated PG. Fresh Kernels suggests ages 8+. Parents need to know that Summer Wars is a PG-rated Japanese animated sci-fi film about a virtual world hacking crisis, family togetherness, and teen romance, suitable for most families.
What movies are like Summer Wars?
If you liked Summer Wars, try The Animatrix, The Mitchells vs. the Machines, Ghost in the Shell: Stand Alone Complex - Solid State Society and Detective Conan: The Phantom of Baker Street.