StepFun: Step3 API

Access StepFun: Step3 from StepFun using Puter.js AI API.

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Model Card

Step3 is a multimodal reasoning model from StepFun built on a Mixture-of-Experts architecture with 321B total parameters (38B active), designed for cost-effective vision-language reasoning. It features innovative Multi-Matrix Factorization Attention (MFA) and Attention-FFN Disaggregation (AFD) for efficient inference across various hardware. The model excels at visual interpretation, complex reasoning, and is available via API or as open-source checkpoints on Hugging Face.

Context Window

N/A

tokens

Max Output

65,536

tokens

Input Cost

$0.57

per million tokens

Output Cost

$1.42

per million tokens

API Usage Example

Add StepFun: Step3 to your app with just a few lines of code.
No API keys, no backend, no configuration required.

<html>
<body>
    <script src="https://js.puter.com/v2/"></script>
    <script>
        puter.ai.chat("Explain quantum computing in simple terms", {
            model: "stepfun-ai/step3"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>

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Get started with Puter.js

Add StepFun: Step3 to your app without worrying about API keys or setup.

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