xAI

Grok 4.3

Grok 4.3 is a Grok model from xAI, released in 2026-04. It costs $1.25 / $2.5 per 1M, has a 256k-token context window, and is best for reasoning, realtime-web-search, agents. Last verified 2026-05-06.

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Spec sheet

Pricing

Input
$1.25 / 1M
Output
$2.5 / 1M
Cached input
$0.3 / 1M
Free tier
No

Context & speed

Context window
256k tokens
Max output
32k tokens
Throughput
~110 tok/s
Time to first token
~600 ms
Speed tier
balanced

Capabilities

Tool use
Yes
Structured output
Yes
Prompt caching
Yes
Extended thinking
Yes
Vision input
Yes
Audio in / out
No
Fine-tuning
No

Deployment

Open weights
No
On-prem
No
HIPAA eligible
No
Zero retention
No
Regions
us

Estimated monthly cost

Assumes typical token shape: 2k input, 600 output per call. Prompt caching is excluded from these figures.

10k calls/mo
$40.00
per month
100k calls/mo
$400.00
per month
1M calls/mo
$4.0k
per month

When to use Grok 4.3

Sweet spot

  • reasoning
  • realtime web search
  • agents
  • x data
  • cheap frontier

Known trade-offs

  • US-only regions
  • younger SDK ecosystem
  • shorter context than Grok 4.20

Works with

xAI SDKOpenAI-compatible APICursorVercel AI SDKOpenRouter

Compare Grok 4.3 to other models

vs Gemini 3 Flashvs Gemini 3.1 Flash-Litevs Qwen3-Maxvs Codestral 25.08vs GLM-5.1vs GPT-5.4 Mini

FAQ — Grok 4.3

How much does Grok 4.3 cost?

Grok 4.3 costs $1.25 / $2.5 per 1M tokens on the xAI API. Cached input reads cost $0.3 per 1M, cutting the input bill by roughly 76% on repeat system prompts.

What is the context window of Grok 4.3?

Grok 4.3 has a 256k-token context window with up to 32k tokens of output. That's enough for long reports, extended chat histories, or structured document analysis.

Does Grok 4.3 have a free tier?

No — X Premium / SuperGrok includes Grok web chat; API is paid.

Is Grok 4.3 HIPAA / EU / on-prem friendly?

Grok 4.3 is not HIPAA-eligible, not available in an EU region, and is API-only. Zero data retention is not available.

What is Grok 4.3 best for?

Grok 4.3 is best for reasoning, realtime web search, agents, x data. Trade-offs to be aware of: US-only regions; younger SDK ecosystem; shorter context than Grok 4.20.

Which tools and SDKs work with Grok 4.3?

Grok 4.3 integrates with xAI SDK, OpenAI-compatible API, Cursor, Vercel AI SDK, OpenRouter. Most major AI frameworks support it either natively or through OpenAI-compatible endpoints.