{"schema":"postcutoff/model@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/m/step-5-preview/","md":"https://postcutoff.com/m/step-5-preview/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"step-5-preview","name":"Step 5 Preview","org":"StepFun","family":"Step 5","released":"2026-09-20","status":"preview","type":"reasoning-llm","modality_in":["text","image","video"],"modality_out":["text"],"open_weights":true,"model_license":"stepfun-model-license-1.0","context_window":1000000,"max_output":64000,"knowledge_cutoff":null,"pricing":{"input":1,"cached_input":0.1,"output":2.7,"unit":"per 1M tokens (USD); reasoning tokens billed as output","source":"https://platform.stepfun.ai/docs/en/guides/pricing/details"},"price_line":"$1 in, $2.70 out per 1M tokens","access":[{"provider":"StepFun API","model_id":"step-5-preview","docs":"https://platform.stepfun.ai/docs/en/guides/models/step-5-preview"},{"provider":"OpenRouter","model_id":"stepfun/step-5-preview","url":"https://openrouter.ai/stepfun/step-5-preview"},{"provider":"Hugging Face","url":"https://huggingface.co/stepfun-ai/Step-5-Preview"},{"provider":"Hugging Face (BF16)","url":"https://huggingface.co/stepfun-ai/Step-5-Preview-BF16"},{"provider":"Hugging Face (NVFP4)","url":"https://huggingface.co/stepfun-ai/Step-5-Preview-NVFP4"},{"provider":"ModelScope","url":"https://modelscope.ai/models/stepfun-ai/Step-5-Preview"}],"capabilities":[{"name":"600B sparse MoE agent model with 1M context and video input","detail":"600B total / 27B active, 92 layers; up to 60 images and short videos per request; reasoning effort low/medium/high.","first":false,"discovered":"launch","source":"https://platform.stepfun.ai/docs/en/guides/models/step-5-preview"}],"entry":"2026-09-20-stepfun-step-5-preview","notes":"Open weights published on 2026-10-15 as promised (FP8, BF16, NVFP4 on Hugging Face; StepFun Model License 1.0: Apache-style, but device makers and MaaS providers over $20M revenue need a commercial licence, attribution above 100M MAU / $20M monthly revenue, and models trained materially on its outputs count as derivatives; see entry 2026-10-15-stepfun-step-5-preview-open-weights). Self-hosting: FP8 on 4x B300 or 8x H200; BF16 on 8x B300 or 16x H200 (model card). Pricing verified on StepFun's own pricing page on 2026-10-13: $1.00 input (cache miss, includes the cache write), $0.10 cache hit, $2.70 output (launch press had reported $0.05 for cache hits). OpenRouter lists it since 2026-10-08 at $1.00 / $2.70 with 1M context and 64k max output. Free and exclusive in Tencent WorkBuddy from Oct 12 to Oct 25, 2026 (Pandaily, citing IT Home).","verified":"2026-10-15","body_md":null,"page_url":"https://postcutoff.com/m/step-5-preview/","events_after":null,"major_after":null,"historic_after":null,"missing_at_launch":null,"events_since_release":1442,"you_url":"https://postcutoff.com/you/step-5-preview/","briefings":null}