About this site
What is JANKEN?
JANKEN (janken.party) is an online rock-paper-scissors battle service for friends. Just create a room, share the link, and play 1v1 or battle royale (up to 500 players) — no install, no signup. Pick a tiebreaker for dinner orders, take a quick break in an online class, or warm up before a video call with overseas friends. The site is localized in Japanese, English, Korean, and Chinese, so cross-border matches just work.
Feedback
Bug reports, feature requests, and just-saying-hi notes are all welcome through the feedback form. Drop anything from "please add this game mode" to "this screen is hard to read on mobile."
Send feedbackSupport the project
Domain, AWS bills, and ongoing maintenance are all self-funded. If JANKEN brought a smile, a coffee on ☕ Buy Me a Coffee keeps the lights on and motivates the next feature.