Models / Free

Nemotron 3.5 Lightning free API

NVIDIA's Nemotron 3.5 Lightning: 30B parameters in total, 3B active per token. It reasons by default; the samples turn reasoning off.

On InferAll it costs $0 per input and output token. A new trial key can call it without a card; paid accounts can call it too. Send this id as the model:

Python (OpenAI SDK)

from openai import OpenAI

client = OpenAI(
    base_url="https://api.inferall.ai/v1",
    api_key="ifu_your_key_here",  # inferall.ai/keys
    default_headers={"X-Inferall-Routing": "exact"},  # answer with this model only
)

response = client.chat.completions.create(
    model="nvidia/nemotron-3.5-lightning-30b-a3b",
    messages=[{"role": "user", "content": "Explain what an API is in one sentence."}],
    max_tokens=300,
    reasoning_effort="none",
)
print(response.choices[0].message.content)

curl

curl https://api.inferall.ai/v1/chat/completions \
  -H "Authorization: Bearer $INFERALL_API_KEY" \
  -H "Content-Type: application/json" \
  -H "X-Inferall-Routing: exact" \
  -d '{"model": "nvidia/nemotron-3.5-lightning-30b-a3b", "messages": [{"role": "user", "content": "Hello"}], "max_tokens": 200, "reasoning_effort": "none"}'

Claude Code and the Anthropic SDK

The same key works on the Anthropic-compatible /v1/messages endpoint:

export ANTHROPIC_BASE_URL=https://api.inferall.ai
export ANTHROPIC_API_KEY=ifu_your_key_here
export ANTHROPIC_MODEL=nvidia/nemotron-3.5-lightning-30b-a3b
export ANTHROPIC_CUSTOM_HEADERS="X-Inferall-Routing: exact"
claude

Good to know

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