How much does the Grok 4.3 API cost?

Grok 4.3 costs $1.25 per million input tokens and $2.5 per million output tokens, with cached input at $0.2 per million. A workload of 10M input and 1.5M output tokens per month costs about $16.25.

What is the context window of Grok 4.3?

Grok 4.3 supports a context window of 1,000,000 tokens (1M).

Is Grok 4.3 open source?

No — Grok 4.3 is a proprietary model available through xAI's API and partner platforms.

What are the best alternatives to Grok 4.3?

The closest alternatives by overall capability are Qwen3-Max, GPT-5.5, Gemini 3 Pro, Gemini 2.5 Pro. See the comparison pages for detailed head-to-head breakdowns.

Grok 4.3

xAI·Apr 2026reasoningproprietary

Grok 4.3 is xAI's flagship, notable for unusually aggressive flagship pricing — $1.25/$2.50 per million tokens with a 1M context window and no fixed output cap. It runs roughly 20% cheaper than its 4.20 predecessor while scoring higher on independent intelligence indices, generates around 168 tokens per second, and set a record 78% non-hallucination rate on the Artificial Analysis Omniscience benchmark. Real-time X data integration remains its signature differentiator.

Benchmark results

No verified benchmark results tracked yet for Grok 4.3. This page is updated as official evaluations are published.

Where it shines

Cheapest output tokens of any frontier flagship
Record-low hallucination rate in independent testing
Very fast generation (~168 tok/s) with a 1M context
Real-time X (Twitter) data integration

Alternatives to Grok 4.3

Qwen3-Max

Alibaba's trillion-parameter API flagship — frontier-adjacent quality with strong agentic tool use at mid-tier prices.

GPT-5.5

OpenAI's flagship reasoning model with a 1M-token context window, built for hard coding, science and long-horizon agentic work.

Gemini 3 Pro

Google's November 2025 frontier breakout — 91.9% GPQA Diamond and 37.5% HLE made it the reasoning leader of its generation.

Gemini 2.5 Pro

Google's 2025 workhorse flagship — first mainstream thinking model with a 1M context, still widely deployed.

Frequently asked questions

How much does the Grok 4.3 API cost?: Grok 4.3 costs $1.25 per million input tokens and $2.5 per million output tokens, with cached input at $0.2 per million. A workload of 10M input and 1.5M output tokens per month costs about $16.25.
What is the context window of Grok 4.3?: Grok 4.3 supports a context window of 1,000,000 tokens (1M).
Is Grok 4.3 open source?: No — Grok 4.3 is a proprietary model available through xAI's API and partner platforms.
What are the best alternatives to Grok 4.3?: The closest alternatives by overall capability are Qwen3-Max, GPT-5.5, Gemini 3 Pro, Gemini 2.5 Pro. See the comparison pages for detailed head-to-head breakdowns.