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NVIDIA Nemotron 120B — free, via the OpenAI API

How to call NVIDIA Nemotron 3 Super 120B at $0 input/output using any OpenAI-compatible SDK. $5 starter pack at /billing activates. Works with Python, TypeScript, LangChain, and Claude Code.

InferAll Team

3 min read
NVIDIA NIMNemotronfree LLM APIOpenAI APIopen sourcedeveloper tools

NVIDIA's Nemotron 3 Super 120B (nvidia/nemotron-3-super-120b-a12b) is one of the most capable open-weight models available today — and it runs at $0 input / $0 output on NVIDIA NIM through InferAll, within the free-plan daily request caps (50 chat / 100 text / day, reset 00:00 UTC). Activate via the $5 starter pack at /billing — the $5 becomes spendable balance for premium providers (OpenAI, Anthropic, Google at the published per-token rate with zero markup).

Here's how to call it using the standard OpenAI SDK:

from openai import OpenAI

client = OpenAI(
    base_url="https://api.inferall.ai/v1",
    api_key="ifu_your_key_here",  # get one at inferall.ai/keys
)

response = client.chat.completions.create(
    model="nvidia/nemotron-3-super-120b-a12b",
    messages=[{"role": "user", "content": "What makes a good system prompt?"}],
    max_tokens=512,
)

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

That's it. The same call works with any OpenAI-compatible library — LangChain, LlamaIndex, LiteLLM, CrewAI, and any other framework that accepts an openai_api_base override.


Why Nemotron 120B

Scale. At 120B parameters, Nemotron outperforms many models twice its cost on reasoning, instruction-following, and long-context tasks. It scores well on coding and math benchmarks without the rate-limit friction of commercial APIs.

Free on NIM. NVIDIA hosts Nemotron on their DGX Cloud infrastructure via NIM (NVIDIA Inference Microservices), which InferAll exposes at $0. There's no inference cost for us to pass through, so it stays free within the allowance.

OpenAI-compatible. The model is served through InferAll's OpenAI-compatible endpoint — you get standard ChatCompletion responses, streaming, tool use, and JSON mode, all working with whatever OpenAI client you already have.


TypeScript / Node.js

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://api.inferall.ai/v1",
  apiKey: process.env.INFERALL_API_KEY,
});

const response = await client.chat.completions.create({
  model: "nvidia/nemotron-3-super-120b-a12b",
  messages: [{ role: "user", content: "Explain backpropagation." }],
});

Streaming

with client.chat.completions.create(
    model="nvidia/nemotron-3-super-120b-a12b",
    messages=[{"role": "user", "content": "Write a poem about distributed systems."}],
    stream=True,
) as stream:
    for chunk in stream:
        print(chunk.choices[0].delta.content or "", end="")

Claude Code / Cline / Cursor

Set these two environment variables and any Anthropic-compatible agent routes through InferAll:

export ANTHROPIC_BASE_URL=https://api.inferall.ai
export ANTHROPIC_API_KEY=ifu_your_key_here

When your agent tries to use claude-opus-4-8, the gateway maps it to Nemotron (opus-class model, same relative capability tier). Works immediately, no configuration changes.


Comparing the free models

All of these are $0 on InferAll, hosted on NVIDIA NIM:

Model Size Best for
nvidia/nemotron-3-super-120b-a12b 120B Complex reasoning, coding, long context
meta/llama-3.1-70b-instruct 70B General chat, instruction following
meta/llama-3.1-8b-instruct 8B Fast responses, simple tasks
mistralai/mistral-medium-3.5-128b 46.7B (MoE) Speed + quality balance

See the live model list for all 40+ free models.


Get a key

inferall.ai/keys — sign up free and start calling (25 free NIM calls before any payment; the $5 starter pack unlocks ongoing use) at /billing. The $5 becomes spendable balance: 40+ open NIM models stay $0 in/out against it (within the free-plan daily request caps); premium providers (OpenAI, Anthropic, Google) bill at the provider's published per-token rate with zero markup.

# Verify the model is live
curl https://api.inferall.ai/ai/v1/models | jq '."nvidia/nemotron-3-super-120b-a12b"'