Model Detail
Step-5-Preview
—Step-5-Preview is an AI model with 302.2B parameters released by stepfun-ai. And supports text+image+video->text inputs, distributed under a other license.
Step-5-Preview is priced at $1/M input tokens and $2.7/M output tokens. Operationally the model offers a 1049K-token context window, which matters when sizing it for prompt-heavy or latency-sensitive workloads. Pricing in this range is the working middle of the API market — neither the cheapest nor the most expensive option per token, so cost-fit is usually a function of how much output you generate.
Step-5-Preview ships with 302.2B parameters. Total weight footprint is approximately 604.3 GB, which is the relevant figure when planning local-inference VRAM. Distribution is governed by the other license — review the exact terms before commercial deployment.
Step-5-Preview is best fit for general-purpose AI workloads, and long-context tasks such as full-codebase analysis or book-length summarization (1049K tokens). Treat this as a starting matrix rather than a benchmark verdict — the right deployment usually depends on the specific evaluation suite that mirrors your workload.
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