Arena AI

Arena AI is a free, community-driven platform that ranks AI models, agents, and coding systems based on millions of real human votes. Unlike static benchmarks, Arena aggregates side-by-side comparisons to produce live rankings that reflect real-world performance. With over 10 million monthly users and 82 million votes, Arena has reached a $100M annualized run rate within eight months of launch, establishing itself as a go-to reference for AI quality. The core experience is Battle Mode, where you can pit two models head-to-head and vote on the better response. Beyond simple chat, Agent Arena runs causal evaluations of AI agents performing real-world tasks, while Fullstack Code Arena lets you build, deploy, and evaluate complete applications with databases, auth, and integrations. A recent addition, the Factuality leaderboard, ranks models by factual accuracy alongside human preference, giving you a clearer picture of reliability. AutoEval is another new tool that provides immediate, calibrated model ratings on real tasks while human votes accumulate, so you get faster feedback without waiting for the full community tally. The platform also supports multimodal comparisons through Multimodal Max, BullshitBench for nonsense detection, and file uploads for images and documents. All public conversations are shared to advance AI research, so the service is free to use. Arena is best for researchers, developers, and AI enthusiasts who want transparent, up-to-date model comparisons. It is not a substitute for private, confidential evaluation; if you need secure testing behind closed doors, consider a dedicated evaluation platform instead.