xAI

xAI: Grok 4.3

x-ai/grok-4.3

Access Grok 4.3 from xAI using Puter.js AI API.

Get Started
// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';

puter.ai.chat("Explain quantum computing in simple terms", {
    model: "x-ai/grok-4.3"
}).then(response => {
    document.body.innerHTML = response.message.content;
});
<html>
<body>
    <script src="https://js.puter.com/v2/"></script>
    <script>
        puter.ai.chat("Explain quantum computing in simple terms", {
            model: "x-ai/grok-4.3"
        }).then(response => {
            document.body.innerHTML = response.message.content;
        });
    </script>
</body>
</html>
# pip install openai
from openai import OpenAI

client = OpenAI(
    base_url="https://api.puter.com/puterai/openai/v1/",
    api_key="YOUR_PUTER_AUTH_TOKEN",
)

response = client.chat.completions.create(
    model="x-ai/grok-4.3",
    messages=[
        {"role": "user", "content": "Explain quantum computing in simple terms"}
    ],
)

print(response.choices[0].message.content)
curl https://api.puter.com/puterai/openai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_PUTER_AUTH_TOKEN" \
  -d '{
    "model": "x-ai/grok-4.3",
    "messages": [
      {"role": "user", "content": "Explain quantum computing in simple terms"}
    ]
  }'

Model Card

Grok 4.3 is xAI's latest flagship reasoning model, designed for agentic workflows, instruction following, and tasks demanding high factual accuracy.

It accepts text and image inputs with always-on reasoning that cannot be disabled. The model supports a 1 million token context window with no output token limit, making it well suited for long-document analysis and multi-step agent tasks. Priced at $1.25 per million input tokens and $2.50 per million output tokens, it delivers improved cost-efficiency over its predecessor Grok 4.20 — scoring higher on the Artificial Analysis Intelligence Index while costing roughly 20% less to run.

Grok 4.3 showed a major jump in real-world agentic task performance, gaining over 300 Elo points on GDPval-AA versus Grok 4.20. It also scores 98% on τ²-Bench Telecom and 81% on IFBench. A strong pick for developers building cost-sensitive agent systems that need reliable tool use and instruction adherence.

Context Window 1M

tokens

Max Output N/A

tokens

Input Cost $1.25

per million tokens

Output Cost $2.5

per million tokens

Release Date Apr 30, 2026

 

Output Speed 216

tokens / sec

Latency 17.44s

time to first token

Model Playground

Try Grok 4.3 instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.

Chat x-ai/grok-4.3
xAI
Chat with Grok 4.3
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Benchmarks

How Grok 4.3 performs on standard evaluations.

Artificial Analysis
Intelligence Index
53.2
Better than 98% of tracked models
Artificial Analysis
Coding Index
41.0
Better than 89% of tracked models
BenchmarkScore
GPQA Diamond Graduate-level science Q&A
90.1%
Humanity's Last Exam Cross-domain reasoning
35.0%
SciCode Scientific programming
47.3%
IFBench Instruction following
81.3%
LCR Long-context reasoning
64.3%
Terminal-Bench Hard Agentic terminal tasks
37.9%
τ²-Bench Tool use / agents
97.7%

Scores sourced from Artificial Analysis.

Find other xAI models

Chat

Grok 4.20

Grok 4.20 is xAI's flagship large language model, offering a rare combination of low hallucination rates and high throughput at competitive pricing. It achieved a record 78% non-hallucination rate on the Artificial Analysis Omniscience benchmark — the highest of any model tested — making it a strong choice for applications where factual reliability matters more than peak reasoning scores. It scored 78.5% on GPQA Diamond and 87.3% on MATH-500. The model supports a 2M-token context window, text and image inputs, parallel function calling, structured outputs, and built-in web search. Reasoning can be toggled on or off per request via API parameter. At $2 per million input tokens and $6 per million output tokens, it's one of the most affordable frontier models available, with output speeds exceeding 230 tokens per second.

Chat

Grok 4.20 Multi-Agent

Grok 4.20 Multi-Agent is a variant of xAI's Grok 4.20 purpose-built for orchestrating multiple AI agents that collaborate on complex, multi-step tasks in real time. Rather than relying on a single inference pass, it coordinates parallel agents that independently search, analyze, and cross-reference information before synthesizing a final response. At low or medium reasoning effort it runs 4 agents; at high or extra-high effort it scales to 16. It scored a 68.7 agentic index on Artificial Analysis — among the highest available. The model shares Grok 4.20's 2M-token context window and natively supports web search, X search, and tool orchestration. It generates up to 2M output tokens per response, making it well suited for deep research workflows, multi-source analysis, and long-running agent pipelines.

Chat

Grok 4.1 Fast

Grok 4.1 Fast is xAI's best tool-calling model released November 2025, featuring a 2M context window and halved hallucination rates versus Grok 4 Fast. It comes in reasoning and non-reasoning modes and is optimized for agentic workflows with native support for web search, X search, and code execution.

Frequently Asked Questions

How do I use Grok 4.3?

You can access Grok 4.3 by xAI through Puter.js AI API. Include the library in your web app or Node.js project and start making calls with just a few lines of JavaScript — no backend and no configuration required. You can also use it with Python or cURL via Puter's OpenAI-compatible API.

Is Grok 4.3 free?

Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Grok 4.3 to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.

What is the pricing for Grok 4.3?
Grok 4.3 costs $1.25 per 1M input tokens and $2.5 per 1M output tokens.
Price per 1M tokens
Input$1.25
Output$2.5
Who created Grok 4.3?

Grok 4.3 was created by xAI and released on Apr 30, 2026.

What is the context window of Grok 4.3?

Grok 4.3 supports a context window of 1M tokens. For reference, that is roughly equivalent to 2,000 pages of text.

How does Grok 4.3 perform on benchmarks?

Grok 4.3 scores 53.2 on the Artificial Analysis Intelligence Index, outperforming 98% of tracked models. On coding, it scores 41.0 (outperforms 89% of models).

Does it work with React / Vue / Vanilla JS / Node / etc.?

Yes — the Grok 4.3 API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.

Get started with Puter.js

Add Grok 4.3 to your app without worrying about API keys or setup.

Read the Docs View Tutorials