Question 1

What is Grok 4.3?

Accepted Answer

Grok 4.3 is a model from xAI, released on Apr 17, 2026. Grok 4 3 is an xAI Grok model for reasoning, coding, vision, and general conversational tasks.

Question 2

How much does Grok 4.3 cost?

Accepted Answer

On the Respan gateway, input starts at $1.25 per 1M tokens on every provider, and output starts at $2.50 per 1M tokens on every provider, after gateway discounts.

Question 3

Which providers serve Grok 4.3 on Respan?

Accepted Answer

3 providers serve Grok 4.3: OpenRouter, Perplexity, and xAI. Perplexity requires your own provider API key (BYOK).

Question 4

What is Grok 4.3's context window?

Accepted Answer

Grok 4.3 accepts up to 1M tokens of context on its largest provider route.

Question 5

How do I use Grok 4.3 with the Respan gateway?

Accepted Answer

Point any OpenAI-compatible SDK at https://api.respan.ai/api/ with your Respan API key and set the model to "xai/grok-4.3". To set it up with a coding agent, copy the agent setup prompt at the top of this page.

Question 6

How fast is Grok 4.3?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was xAI at 74 tokens per second, and the lowest response latency was 1.7 seconds on OpenRouter. Speed varies with request size and provider.

Question 7

Where does Grok 4.3 rank on the Respan Index?

Accepted Answer

Grok 4.3 scores 20.7 out of 100 on the Respan Index v1.1, ranking #92 of 138 models. By category: Coding 5.8, Agents 6.1, Reasoning 28.2, Knowledge & language 32.8, and Human preference 49.1. The Respan Index combines independent and lab-reported benchmark results into one score, using benchmark data collected by llmmetric.com.

Question 8

How does Grok 4.3 score on benchmarks?

Accepted Answer

Grok 4.3 has 22 published benchmark scores, including LiveBench Coding 69.9%, LiveBench Agentic Coding 18.5%, and GPQA Diamond 88.8%. Each score links to where it was published; the data is collected by llmmetric.com.

Provider	Context	Input	Output
OpenRouter`openrouter/x-ai/grok-4.3`	1M	$1.25/M	$2.50/M
PerplexityBYOK only`perplexity/xai/grok-4.3`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.3`	1M	$1.25/M	$2.50/M

Grok 4.3

Providers

Certified where it counts.

Pricing

Cost by volume

Throughput and latency

Output speed

Response latency

Benchmarks

Respan Indexv1.1

Coding2

Agents

Apps

Grok 4.3 FAQ

Works with your entire stack

Built for AI agents.
Break less.
Ship more.

Reasoning4

Math6

Knowledge4

Arena3

Other1