StepFun: Step 3.5 Flash - API in Egypt, billed in EGP

Live
stepfunstep-3.5-flash

Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parameters per token

Modality

Chat

Context window

262K tokens

Max output

66K tokens

Region

US

Published

29 Sept 2026

Pricing

Input

5.73

EGP per 1M tokens

Output

17.19

EGP per 1M tokens

Monthly cost example

544.37 EGP

Illustrative estimate: 50M input + 15M output tokens per month at this model's catalog rates.

Use it via the API

StepFun: Step 3.5 Flash works with any OpenAI-compatible SDK — point the base URL at https://dev-backend.sovereigneg.com/v1 and use your SovereignEG API key.

Run inference

OpenAI-compatible — POST /v1/chat/completions — drop-in for any OpenAI SDK.

from openai import OpenAI

client = OpenAI(
    base_url="https://dev-backend.sovereigneg.com/v1",
    api_key="YOUR_API_KEY",
)

response = client.chat.completions.create(
    model="step-3.5-flash",
    messages=[
        {"role": "user", "content": "What are some fun things to do in Cairo?"}
    ],
)

print(response.choices[0].message.content)

Frequently asked questions

How much does StepFun: Step 3.5 Flash cost?

5.73 EGP per 1M input tokens; 17.19 EGP per 1M output tokens. Billing is metered per token in Egyptian pounds (EGP), with no minimum commitment.

What is the context window of StepFun: Step 3.5 Flash?

StepFun: Step 3.5 Flash supports a context window of 262,144 tokens (262K), with up to 65,536 output tokens per response.

Where is StepFun: Step 3.5 Flash hosted?

StepFun: Step 3.5 Flash is served from US (US-hosted inference).

How do I use StepFun: Step 3.5 Flash via the API?

StepFun: Step 3.5 Flash is available through the OpenAI-compatible SovereignEG API: point your SDK's base URL at https://dev-backend.sovereigneg.com/v1 and call /v1/chat/completions with model "step-3.5-flash" and your API key.