Step 3.7 Flash is StepFun's latest high-efficiency multimodal Mixture-of-Experts model. It pairs a 196B-parameter language backbone with a vision encoder for na
No signup required — try it as a guest. 30,000 free tokens every day once you sign up.
Step 3.7 Flash is StepFun's latest high-efficiency multimodal Mixture-of-Experts model. It pairs a 196B-parameter language backbone with a vision encoder for native image and video understanding, activating roughly 11B parameters...
Very large context window — 256,000 tokens (paste entire codebases or long PDFs).
Extremely low per-token price compared to frontier models — good for high-volume workloads.
Hosted by Stepfun — you can access it here alongside GPT-4o, Claude, Gemini and 100+ more on one plan.
Switch to any other model mid-conversation from the picker.
Around 750–1,875 tokens per typical message. 15M Pro tokens buy roughly 8,000–20,000 messages.
OpenAI-compatible. Same Faceb.ai tokens cover chat and API. Drop-in replacement for the OpenAI SDK.
curl https://api.faceb.ai/v1/chat/completions \
-H "Authorization: Bearer sk-faceb-YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "stepfun/step-3.7-flash",
"messages": [{"role": "user", "content": "Hello!"}],
"stream": true
}'from openai import OpenAI
client = OpenAI(
base_url="https://api.faceb.ai/v1",
api_key="sk-faceb-YOUR_KEY",
)
stream = client.chat.completions.create(
model="stepfun/step-3.7-flash",
messages=[{"role": "user", "content": "Hello!"}],
stream=True,
)
for chunk in stream:
print(chunk.choices[0].delta.content or "", end="", flush=True)import OpenAI from "openai";
const client = new OpenAI({
baseURL: "https://api.faceb.ai/v1",
apiKey: "sk-faceb-YOUR_KEY",
});
const stream = await client.chat.completions.create({
model: "stepfun/step-3.7-flash",
messages: [{ role: "user", content: "Hello!" }],
stream: true,
});
for await (const chunk of stream) {
process.stdout.write(chunk.choices[0]?.delta?.content || "");
}
Also works for image generation (image-output model slugs return image_url content parts) and web search (add "web_search": true to the payload). Same endpoint, same wallet.
Step 3.7 Flash is a chat/completion model served by Stepfun and accessed through Faceb.ai. Try it without signing up — guest users get a small pool of session tokens to experiment.
You get 30,000 tokens free every day — usually enough for a handful of messages a day on this model. Need more? Pro is $14.99/month for 15M tokens, or top-ups from $5.
256,000 tokens. Paste your source material in, no need to truncate.
Yes. Any API key from /account/api/ works with model slug `stepfun/step-3.7-flash`. The OpenAI SDK works with base_url=https://api.faceb.ai/v1.
Depends on the task. Faceb.ai lets you switch models per message — benchmark side-by-side by asking both the same prompt, which is more reliable than abstract comparisons.
Around 750–1,875 tokens per typical message. 15M Pro tokens buy roughly 8,000–20,000 messages.
No. We contractually request that upstream providers not train on content routed through us. Your chat history lives only on your account.
It depends on the model size and training mix. For serious code work the developer favourites are Claude 3.5 Sonnet and DeepSeek V3; for quick edits, most capable models work fine.
Yes — point your SDK at https://api.faceb.ai/v1 and use this model's slug as the model parameter. Everything else works as normal.
Check the model catalog — multimodal models are marked in the picker. If it accepts images, you can drop screenshots and diagrams straight into the chat.
Yes — the picker is always at the top of the chat. Previous context carries over.
Yes. Our catalog auto-fetches from the upstream aggregator, so provider updates and new versions appear in the picker as soon as they're available.
Your Faceb.ai tokens work for every model — switch per message, no extra subscriptions.
OpenAI's flagship multimodal model — text, vision, and code.
Chat with GPT-4o →OpenAI's fastest, cheapest frontier model — great default.
Chat with GPT-4o mini →Anthropic's best balance of quality and cost — a coder favourite.
Chat with Claude 3.5 Sonnet →One subscription covers every frontier model — switch between them per message. No extra API keys, no extra bills.