DeepInfra

Stepfun Ai/Step 3.5 Flash

Name: Stepfun Ai/Step 3.5 Flash
Brand: DeepInfra
Price: 0.1 USD
Availability: InStock

Stepfun Ai/Step 3.5 Flash is a large language model by DeepInfra. Priced at $0.1 per million input tokens and $0.3 per million output tokens, it is one of the most cost-efficient options in its class. Access Stepfun Ai/Step 3.5 Flash through Inworld Router with OpenAI SDK compatibility, built-in failover, and intelligent routing across providers.

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Use This Model

Step 1 — Create Router

curl --location 'https://api.inworld.ai/router/v1/routers' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "name": "compare-frontier-models",
  "defaultRoute": {
    "route_id": "default",
    "variants": [
      {
        "variant": {
          "variant_id": "deepinfra/stepfun-ai/Step-3.5-Flash-a",
          "model_id": "deepinfra/stepfun-ai/Step-3.5-Flash"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "deepinfra/XiaomiMiMo/MiMo-V2.5-b",
          "model_id": "deepinfra/XiaomiMiMo/MiMo-V2.5"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "deepinfra/stepfun-ai/Step-3.5-Flash-c",
          "model_id": "deepinfra/stepfun-ai/Step-3.5-Flash"
        },
        "weight": 34
      }
    ]
  }
}'

import requests

response = requests.post(
    "https://api.inworld.ai/router/v1/routers",
    headers={
        "Authorization": "Basic <your-api-key>",
        "Content-Type": "application/json",
    },
    json={
        "name": "compare-frontier-models",
        "defaultRoute": {
            "route_id": "default",
            "variants": [
                {
                    "variant": {
                        "variant_id": "deepinfra/stepfun-ai/Step-3.5-Flash-a",
                        "model_id": "deepinfra/stepfun-ai/Step-3.5-Flash"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "deepinfra/XiaomiMiMo/MiMo-V2.5-b",
                        "model_id": "deepinfra/XiaomiMiMo/MiMo-V2.5"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "deepinfra/stepfun-ai/Step-3.5-Flash-c",
                        "model_id": "deepinfra/stepfun-ai/Step-3.5-Flash"
                    },
                    "weight": 34
                }
            ]
        }
    },
)
print(response.json())

const response = await fetch(
  "https://api.inworld.ai/router/v1/routers",
  {
    method: "POST",
    headers: {
      Authorization: "Basic <your-api-key>",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      name: "compare-frontier-models",
      defaultRoute: {
        route_id: "default",
        variants: [
          {
            variant: {
              variant_id: "deepinfra/stepfun-ai/Step-3.5-Flash-a",
              model_id: "deepinfra/stepfun-ai/Step-3.5-Flash",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "deepinfra/XiaomiMiMo/MiMo-V2.5-b",
              model_id: "deepinfra/XiaomiMiMo/MiMo-V2.5",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "deepinfra/stepfun-ai/Step-3.5-Flash-c",
              model_id: "deepinfra/stepfun-ai/Step-3.5-Flash",
            },
            weight: 34,
          },
        ],
      },
    }),
  }
);
const data = await response.json();
console.log(data);

Step 2 — Chat Completion

curl --location 'https://api.inworld.ai/v1/chat/completions' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "model": "inworld/compare-frontier-models",
  "messages": [{"role": "user", "content": "Hello!"}]
}'

Stepfun Ai/Step 3.5 Flash pricing and providers

Access Stepfun Ai/Step 3.5 Flash through DeepInfra via Inworld Router or Realtime API. By using the AI provider(s) below you acknowledge you reviewed and agree to their terms listed in the Legal section under the AI provider's name.