Qwen3.5-4B by SiliconFlow

Create a key on the China site (cloud.siliconflow.cn) and call the OpenAI-compatible endpoint. The model is priced at 0 there; the international site may charge for it.

Access
Free API tier
Free limits
Free on siliconflow.cn · limits not published
Modality
text
Credit card
Not required
Commercial use
Unclear, verify
Context window
262,144 tokens
Model ID
Qwen/Qwen3.5-4B
Base URL
https://api.siliconflow.cn/v1
Checked
Nov 11, 2026

Quickstart

curl https://api.siliconflow.cn/v1/chat/completions \
  -H "Authorization: Bearer $KEY" \
  -d '{"model":"Qwen/Qwen3.5-4B","messages":[{"role":"user","content":"hi"}]}'

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Frequently asked

Is Qwen3.5-4B free?

Yes. SiliconFlow offers it as Free API tier with these limits: Free on siliconflow.cn · limits not published. No credit card is required.

Can I use Qwen3.5-4B commercially?

Commercial terms are not clearly documented. Check the provider's current terms before shipping.

How do I start using Qwen3.5-4B?

Get a free API key from the provider dashboard. Set the base URL to https://api.siliconflow.cn/v1 and the model to Qwen/Qwen3.5-4B. Create a key on the China site (cloud.siliconflow.cn) and call the OpenAI-compatible endpoint. The model is priced at 0 there; the international site may charge for it.

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