When was Grok 4 Fast released?

Grok 4 Fast was released on August 28, 2025 by xAI. This is the official Grok 4 Fast release date tracked on LLM Stats.

How much does Grok 4 Fast cost?

Grok 4 Fast pricing starts at $0.20 per million input tokens and $0.50 per million output tokens via xAI, the lowest price among tracked providers.

Is Grok 4 Fast available via API?

Yes, Grok 4 Fast is available via API. See the official documentation for authentication and endpoint details. It is served by 1 provider tracked on LLM Stats.

Who created Grok 4 Fast?

Grok 4 Fast was created by xAI.

What is the license for Grok 4 Fast?

Grok 4 Fast is released under the Proprietary license.

Is Grok 4 Fast multimodal?

Yes, Grok 4 Fast is multimodal and can accept both text and images as input.

Where can I use Grok 4 Fast?

Grok 4 Fast is available through 1 provider including xAI.

Where is the Grok 4 Fast paper or technical report?

Grok 4 Fast has a paper or technical report available at https://data.x.ai/2025-08-26-grok-code-fast-1-model-card.pdf. Use that source for architecture, training, release and evaluation details.

What models should I compare Grok 4 Fast against?

Common Grok 4 Fast comparisons include Grok 4 Fast vs Grok-3 Mini, Grok 4 Fast vs LongCat-Flash-Thinking, Grok 4 Fast vs Grok-4 Heavy. Compare them side by side for benchmark scores, pricing, context window, latency and API availability.

Grok 4 Fast API Pricing, Context Window & Benchmarks

Name: Grok 4 Fast
Author: xAI

Grok 4 Fast: API Pricing, Context Window & Benchmarks

Grok 4 Fast is a language model from xAI, released in August 2025, with multimodal input.

Grok 4 Fast is a high-speed variant of Grok-4, optimized for faster inference while maintaining strong reasoning capabilities. It offers improved throughput and lower latency compared to the standard Grok-4 model.

Input

TextImage

Output

Text

Grok 4 Fast benchmarks

Capability tiers

Standing within each category, adjusted for leaderboard depth.

Real tasks performance

High-confidence performance for Grok 4 Fast across real-world prompt categories. Only 95% intervals at most 4 points wide are shown.

Performance by conversation depth

How Grok 4 Fast holds up as conversations get longer.

Quality Tracker

Grok 4 Fast Performance Across Datasets

Scores sourced from the model's scorecard, paper, or official blog posts

llm-stats.com - Fri Sep 04 2026

Notice missing or incorrect data?

Grok 4 Fast pricing

Providers

Grok 4 Fast starts at $0.200 per million input tokens and $0.500 per million output tokens via xAI.

Provider	Input $/M	Cached input $/M	Output $/M	Context in / out	TTFT p95 s	Output p5 c/s	Modalities in / out
xAI	$0.200	—	$0.500	2.0M/30.0K	—	—	/

Cached input is the discounted price for prompt tokens served from a provider cache. TTFT is time to first token. Output is characters per second; p5 is the sustained floor exceeded by 95% of observed requests.

Grok 4 Fast context window

Input and output token limits for Grok 4 Fast, plus how it ranks on long-context understanding.

InputOutput

2Mtokens

30Ktokens

≈ 3.0k pages of text

8K128K1M

Grok 4 Fast API

Available from the model provider

Grok 4 Fast has an official provider API. It is not currently routed through the LLM Stats gateway.

Read the official API documentation

Grok 4 Fast latency

Grok 4 Fast time to first token, sustained output throughput, and failed-request rate from live API traffic over the trailing 7 days.

Grok 4 Fast examples

Recent arena outputs from Grok 4 Fast, picked from the highest-ranked matchups.

Grok 4 Fast license

Grok 4 Fast is a proprietary model available under its provider's product and API terms.

License: Proprietary; Hosted access

Proprietary license - usage restrictions apply

Grok 4 Fast resources

Official sources for Grok 4 Fast: api documentation, paper or system card.

Grok 4 Fast vs other models

The most-compared alternatives to Grok 4 Fast are Grok-3 Mini, LongCat-Flash-Thinking, Grok-4 Heavy. Open any pair side-by-side for benchmarks, pricing, context, and latency.