Grok 4.1 Fast vs MiMo-V2-Flash

Grok 4.1 Fast

xAI

Grok 4.1 Fast, released by xAI in November 2025, is a fast-response variant from the Grok 4 family featuring a 2M token context window designed for high-throughput applications. It omits thinking tokens for immediate responses, reducing latency while maintaining strong output quality. Grok 4.1 Fast targets production APIs, real-time assistants, and cost-sensitive applications requiring long-context understanding at high volume.

Xiaomi

MiMo-V2-Flash, released by Xiaomi on December 16, 2025, is a Mixture-of-Experts large language model with 309 billion total parameters and 15 billion active parameters per inference, designed for high-speed reasoning and agentic workflows. It features a 256K token context window, processes up to 150 tokens per second, and was trained on 27 trillion tokens. MiMo-V2-Flash targets open-source deployments requiring fast, capable coding and reasoning with an efficient inference footprint, under an MIT license.