StepFun: Step 3.5 Flash - API in Egypt, billed in EGP
Livestep-3.5-flashStep 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)import OpenAI from "openai"
const client = new OpenAI({
baseURL: "https://dev-backend.sovereigneg.com/v1",
apiKey: "YOUR_API_KEY",
})
const response = await client.chat.completions.create({
model: "step-3.5-flash",
messages: [
{ role: "user", content: "What are some fun things to do in Cairo?" },
],
})
console.log(response.choices[0].message.content)curl https://dev-backend.sovereigneg.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "step-3.5-flash",
"messages": [
{"role": "user", "content": "What are some fun things to do in Cairo?"}
]
}'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.
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