--- format: "aidr-story-markdown/v1" id: "44989556a554578e89a66635fc341243e878a8128af277ac1a09901ab29a2bda" canonical_url: "https://aidr.today/44989556?lang=en" title: "StepFun Releases 600B Parameter Step 5 Preview With Open Weights on Oct 15" lang: "en" requested_lang: "en" available_langs: ["en","vi"] translation_fallback: null fallback_fields: [] published_at: "2026-09-21T14:56:12.000Z" category: "Models" topics: ["stepfun","step-5","open-weights","llm","market-brief","model","releases","api"] source_urls: ["https://marketbrief.now/ai/stepfun-releases-600b-parameter-step-5-preview-with-open-weights-on-oct-2959efce","https://x.com/AdinaYakup/status/2101977570958885005","https://x.com/omarsar0/status/2102035017262149640","https://huggingnews.com/ai/stepfun-releases-600b-parameter-step-5-preview-with-open-weights-on-oct-2959efce","https://huggingnews.com/ai/stepfun-launches-600b-parameter-step-5-model-and-opens-weights-oct-15-f167f39f","https://marketbrief.now/ai/stepfun-launches-600b-parameter-step-5-model-and-opens-weights-oct-15-f167f39f","https://x.com/ArtificialAnlys/status/2102213621963243704","https://x.com/ArtificialAnlys/status/2102213629911384336"] summary: "Step 5 Preview supports a 1 million token context window and vision capabilities to automate professional knowledge work and software engineering. The Mixture-…" --- # StepFun Releases 600B Parameter Step 5 Preview With Open Weights on Oct 15 > [Open the canonical story]() **Published:** 2026-09-21T14:56:12.000Z **Category:** Models **Topics:** stepfun, step\-5, open\-weights, llm, market\-brief, model, releases, api ## Summary Step 5 Preview supports a 1 million token context window and vision capabilities to automate professional knowledge work and software engineering\. The Mixture\-… ## Sources - [Story source]() - [Story source]() - [Supporting source]() - [Story source]() - [Story source]() - [Story source]() - [Story source]() - [Supporting source]()