grok-4.20· Released Mar 31, 2026

x-ai/grok-4.20

Grok 4.20 is a reasoning model from xAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering...

Input

From$1.04156/M

Output

From$2.08313/M

Context

Up to 2M

Max output

—

Modalities

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Input and output show the lowest price across upstreams, for reference. Your actual prices are listed per upstream below.

Upstreams & pricing

Upstream	Context	Max output	Input $/1M	Output $/1M	Cached input $/1M	Data policy
Zenlayer AI Gateway-openai_compat/GlobalFrom price	2M	—	$1.04156	$2.08313	$0.16665	—

Routed in real time — you pay the listed price of whichever upstream serves your call. Data policies reflect each upstream's own data terms and its agreement with us. We do not independently audit upstream implementations.

How to call

bashrequest.sh

curl https://api.lune.io/v1/chat/completions \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "x-ai/grok-4.20",
    "messages": [
      {"role": "user", "content": "Say hello in five words."}
    ]
  }'

pythonrequest.py

from openai import OpenAI
import os

client = OpenAI(
    api_key=os.environ["API_KEY"],
    base_url="https://api.lune.io/v1",
)

resp = client.chat.completions.create(
    model="x-ai/grok-4.20",
    messages=[{"role": "user", "content": "Say hello in five words."}],
)

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

tsrequest.ts

import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.API_KEY,
  baseURL: "https://api.lune.io/v1",
});

const resp = await client.chat.completions.create({
  model: "x-ai/grok-4.20",
  messages: [{ role: "user", content: "Say hello in five words." }],
});

console.log(resp.choices[0].message.content);

gomain.go

package main

import (
    "context"
    "fmt"
    "os"

    "github.com/sashabaranov/go-openai"
)

func main() {
    cfg := openai.DefaultConfig(os.Getenv("API_KEY"))
    cfg.BaseURL = "https://api.lune.io/v1"
    client := openai.NewClientWithConfig(cfg)

    resp, err := client.CreateChatCompletion(
        context.Background(),
        openai.ChatCompletionRequest{
            Model: "x-ai/grok-4.20",
            Messages: []openai.ChatCompletionMessage{
                {Role: "user", Content: "Say hello in five words."},
            },
        },
    )
    if err != nil {
        panic(err)
    }
    fmt.Println(resp.Choices[0].Message.Content)
}