xAIFree
Grok 4 Heavy
API model name: grok-4-heavy
Grok 4 Heavy is xAI's chat model, served on the Api.Airforce unified API. It is available on the free tier at no per-token cost. Access it through the OpenAI-compatible API with one key, alongside 65+ other models on Api.Airforce.
Pricing
Specifications
- Provider
- xAI
- Type
- chat model
Use Grok 4 Heavy via the API
OpenAI-compatible — point any OpenAI SDK at https://api.airforce/v1 and pass grok-4-heavy as the model.
cURL
curl https://api.airforce/v1/chat/completions \
-H "Authorization: Bearer $AIRFORCE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "grok-4-heavy",
"messages": [{ "role": "user", "content": "Hello!" }]
}'Python
from openai import OpenAI
client = OpenAI(base_url="https://api.airforce/v1", api_key="$AIRFORCE_API_KEY")
r = client.chat.completions.create(
model="grok-4-heavy",
messages=[{"role": "user", "content": "Hello!"}],
)
print(r.choices[0].message.content)JavaScript
import OpenAI from "openai";
const client = new OpenAI({ baseURL: "https://api.airforce/v1", apiKey: process.env.AIRFORCE_API_KEY });
const r = await client.chat.completions.create({
model: "grok-4-heavy",
messages: [{ role: "user", content: "Hello!" }],
});
console.log(r.choices[0].message.content);Live performance
Real throughput and latency across the suppliers serving this model.
Loading live metrics…
Related models
Grok 4xAI · $0.70 / 1MGrok 4 FreexAI · FreeGrok 4 ThinkingxAI · $1.80 / 1MGrok 4.1 ExpertxAI · $1.80 / 1MGrok 4.1 FastxAI · Free / 1MGrok 4.1 Fast FreexAI · FreeGrok 4.1 Fast Non ReasoningxAI · $0.18 / 1MGrok 4.1 Fast ReasoningxAI · $0.50 / 1MGrok 4.1 MinixAI · FreeGrok 4.2xAI · $0.71 / 1MGrok 4.20 BetaxAI · FreeClaude 3 7 Ch ExpAnthropic · Free