Mixpanel founder Suhail launches Particle with a model that claims 45% token savings

Particle-1, a post-trained version of DeepSeek V4.1 Flash, says it matches accuracy while using roughly 45% fewer output tokens Suhail, the founder and former CEO of Mixpanel, has a new company. It is called Particle, and its pitch fits in one sentence: same answers, fewer words. On October 28, 2026, Suhail announced the San Francisco-based AI startup alongside its first model, Particle-1. The company says the model uses about 45% fewer output tokens on average during evaluations while keeping its accuracy intact. In an industry that bills by the token, that is less a footnote and more the whole business model. What Particle-1 actually is Particle-1 is not built from scratch. It is a post-trained version of DeepSeek V4.1 Flash, an existing model that Particle took and refined. The tuning came through reinforcement learning, according to the research findings on the launch. Reinforcement learning is a training method where a model gets rewarded for desirable behavior. In this case, the desired behavior was reaching the right answer without rambling on the way there. The model is aimed at developers first. Particle says its initial focus is software engineering workloads, with plans ...