Question 1

What is Grok 4.20 Reasoning?

Accepted Answer

Grok 4.20 Reasoning is a model from xAI, released on Mar 10, 2026. Grok 4 20 0309 is an xAI Grok model for reasoning, coding, vision, and general conversational tasks.

Question 2

How much does Grok 4.20 Reasoning 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 4.20 Reasoning on Respan?

Accepted Answer

11 providers serve Grok 4.20 Reasoning: Perplexity, Google Vertex AI, and xAI. Perplexity and Google Vertex AI require your own provider API key (BYOK).

Question 4

What is Grok 4.20 Reasoning's context window?

Accepted Answer

Grok 4.20 Reasoning accepts up to 1M tokens of context on its largest provider route.

Question 5

How do I use Grok 4.20 Reasoning 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-4.20-reasoning-gv2". 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 4.20 Reasoning?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was xAI at 103 tokens per second, and the lowest response latency was 2.2 seconds on xAI. Speed varies with request size and provider.

Question 7

How does Grok 4.20 Reasoning score on benchmarks?

Accepted Answer

Grok 4.20 Reasoning has 10 published benchmark scores, including GPQA Diamond 89.3%, OTIS Mock AIME 2024-2025 92.2%, and SimpleQA Verified 30.2%. Each score links to where it was published; the data is collected by llmmetric.com.

Provider	Context	Input	Output
PerplexityBYOK only`perplexity/xai/grok-4.20-reasoning`	1M	$1.25/M	$2.50/M
Google Vertex AIBYOK only`vertex_ai/xai/grok-4.20-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-0309-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-beta-0309-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-beta-latest-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-beta-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-experimental-beta-0304-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-experimental-beta-reasoning-latest`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-reasoning`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-reasoning-gv2`	1M	$1.25/M	$2.50/M
xAI`xai/grok-4.20-reasoning-latest`	1M	$1.25/M	$2.50/M

Grok 4.20 Reasoning

Providers

Certified where it counts.

Pricing

Cost by volume

Throughput and latency

Output speed

Response latency

Benchmarks

Reasoning2

Math5

Knowledge2

Other1

Apps