Arena (formerly Chatbot Arena) vs HELM

Arena, formerly Chatbot Arena, is a free web platform for evaluating AI models by comparing responses and collecting votes for public leaderboards. In Battle mode, it presents two anonymous responses and reveals the model identities after a vote. Arena aggregates qualifying votes with the Bradley-Terry rating system. Side by Side and Direct modes are also available, but only anonymous Battle votes count toward official rankings. Leaderboards cover agent, text, web development, image, video, vision, document and search tasks; comparisons include image generation, image editing and video generation. Leaderboards can be viewed without signing in, while Direct, Side by Side, Image Arena and Video Arena require login. Accounts can use Google or email, and coding Agent Mode can connect to GitHub repositories. Arena applies a daily usage limit that resets 24 hours after it is reached. Video Arena requires login, permits two generations per 24 hours and offers Battle mode only. Arena also provides commercial evaluation services for enterprises, model labs and developers, with results supported by service-level agreements. Conversations may be used in research datasets and private provider evaluations; shared data is de-identified, and Arena advises against submitting sensitive information.

HELM is an open-source Python framework for evaluating foundation models, including large language and multimodal systems. It supplies standardized datasets and benchmarks such as MMLU-Pro, GPQA, IFEval, and WildBench, with a unified interface for models from providers including OpenAI, Anthropic, and Google. Evaluations can examine accuracy, efficiency, bias, and toxicity, and can include custom metrics, LLM-as-a-judge checks, safety evaluations, and human review workflows. Users can configure private checkpoints or model servers, run inference locally, or send requests to an API. A web interface displays individual prompts and responses, while leaderboards compare models and benchmarks across areas such as medicine, finance, multilinguality, and world knowledge. HELM can reproduce published evaluation results and documents commands for running benchmarks, summarizing results, and starting a local server. It is free, Apache-2.0 licensed, and entered maintenance mode on June 1, 2026.