Grok 4.3

x-ai/grok-4.3

Grok 4.3 is an xAI reasoning model that xAI describes as fast and reliable, with strong tool calling and instruction following. It accepts text and image input with text output, offers a 1M-token context window, and supports configurable reasoning effort that can be switched off or raised, defaulting to low. It suits agentic workflows, long-document analysis and high-volume instruction-following tasks, while Grok 4.5 through 4.7 later took over as xAI's flagship for coding.

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Input price: $1.25USD / 1M tokens
Output price: $2.50USD / 1M tokens
Context window: 1M
Max output: 1M

Production route

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Prompt

Image URL or upload

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1M context1M max outputVision

Input$1.25/MOutput$2.50/MCache read$0.20/M

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Model card

Specifications

Pricing

Input: $1.25 / 1M tokens
Output: $2.50 / 1M tokens
Cache read: $0.20 / 1M tokens

Context & modalities

Context window: 1,000,000 tokens
Max output: 1,000,000 tokens
Input: Text, image
Output: Text

Capabilities

Chat: Supported
Vision: Supported
Reasoning: Supported
Structured output: Supported
Function calling: Supported
Audio input: Not supported

Access

Provider: xAI
Model ID: x-ai/grok-4.3
Execution: sync
Base URL: https://api.sandbase.ai
API: Chat Completions API
Endpoint: /v1/chat/completions

Independent evaluations

Benchmarks

Scores on standardized evaluations, compared with other models on SandBase.

Metrics sourced from Artificial Analysis · Intelligence Index v4.3

Artificial Analysis Intelligence Index: a composite of ten evaluations across reasoning, knowledge, math and coding. Higher is better. Grok 4.3 ranks #53 of 87 models on SandBase.

Start building

Send your first request

OpenAI-compatible endpoint with unified authentication and usage tracking.

Production API

Chat Completions API endpoint

https://api.sandbase.ai/v1/chat/completions

Model ID

x-ai/grok-4.3

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/chat/completions" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "x-ai/grok-4.3",
  "messages": [
    {
      "role": "user",
      "content": "Hello"
    }
  ],
  "max_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
Grok 4.3This model `xAI`	1M	$1.25	$2.50	Apr 30, 2026
Grok 4.7 `xAI`	488.3K	$2.00	$6.00	Sep 21, 2026
Grok 4.6 `xAI`	488.3K	$2.00	$6.00	Aug 12, 2026
Grok 4.5 `xAI`	488.3K	$2.00	$6.00	Jul 8, 2026

Questions

FAQ

How do I call xAI Grok 4.3 through SandBase?

Create a SandBase API key, then send requests with the model ID "x-ai/grok-4.3" to Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.

How much does xAI Grok 4.3 cost?

$1.25 per 1M input tokens and $2.50 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

What is the context window of xAI Grok 4.3?

1M tokens of context, with up to 1M output tokens per response.

How does xAI Grok 4.3 score on benchmarks?

xAI Grok 4.3 scores 24.9 on the Artificial Analysis Intelligence Index (v4.3), ranking #53 of 87 models on SandBase; Coding Index 42.2, Agentic Index 15.5. Source: Artificial Analysis, measured as Grok 4.3 (High).

Which features does xAI Grok 4.3 support?

xAI Grok 4.3 supports vision (image input), reasoning, function calling, structured output. See Specifications above for the full list.

Do I need a separate xAI account?

No. One SandBase API key and balance gives you access to xAI Grok 4.3 and the other models in the catalog; you do not need to sign up with xAI separately.