xAI · current

grok-4-fast-reasoning

grok-4-fast-reasoning is attributed to xAI in the catalog. It accepts text and image input and produces text output. Reported capabilities include reasoning and tool calling.

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Modalities

Hosted provider token rates

$0.20 / $0.50

USD per 1M input / output tokens · 302.AI

Context

Released

2025-12-18

Knowledge cutoff

Jun 2025

No recent lab-operated provider rate is available. Showing the third-party host with the lowest input rate + ¼ output rate. This is one offering, not an average; other providers, modalities, tiers, and fees may differ.

Where to use it

5 observed offerings · token prices in USD per million where available

Estimate your workload cost

Jiekou.AI

grok-4-fast-reasoning

deprecated

Input

$0.18

Output

$0.45

Cache

—

Context

Max output

Reasoning: Yes
Tool calling: Yes
Structured output: Yes
Temperature: Yes

Not a current offering

Poe

xai/grok-4-fast-reasoning

deprecated

Input

$0.20

Output

$0.50

Cache

$0.05

Context

Max output

128K

Reasoning: Yes
Tool calling: Yes
Structured output: Unknown
Temperature: No

Not a current offering

302.AI

grok-4-fast-reasoning

current

Input

$0.20

Output

$0.50

Cache

—

Context

Max output

30K

Reasoning: Yes
Tool calling: Yes
Structured output: Unknown
Temperature: Yes

Recent price

Helicone

grok-4-fast-reasoning

current

Input

$0.20

Output

$0.50

Cache

$0.05

Context

Max output

Reasoning: Yes
Tool calling: Yes
Structured output: Unknown
Temperature: Yes

Recent price

Qiniu

x-ai/grok-4-fast-reasoning

deprecated

Input

—

Output

—

Cache

—

Context

Max output

Reasoning: Yes
Tool calling: Yes
Structured output: No
Temperature: Yes

Not a current offering

Limits and capabilities reflect each provider’s listed offering. Unknown means support was not reported.

Provider / API ID	Status	Context	Max output	Input	Output	Cache read	Reasoning	Tools	Structured	Temperature
Jiekou.AI grok-4-fast-reasoning	deprecatedNot a current offering	2M	2M	$0.18	$0.45	—	Yes	Yes	Yes	Yes
Poe xai/grok-4-fast-reasoning	deprecatedNot a current offering	2M	128K	$0.20	$0.50	$0.05	Yes	Yes	Unknown	No
302.AI grok-4-fast-reasoning	currentRecent price	2M	30K	$0.20	$0.50	—	Yes	Yes	Unknown	Yes
Helicone grok-4-fast-reasoning	currentRecent price	2M	2M	$0.20	$0.50	$0.05	Yes	Yes	Unknown	Yes
Qiniu x-ai/grok-4-fast-reasoning	deprecatedNot a current offering	2M	2M	—	—	—	Yes	Yes	No	Yes

Capabilities and limits

Input: text, image
Output: text
Max output: 30K
Weights: Closed (source-reported)
Release: 2025-12-18
Knowledge cutoff: Jun 2025
Family: grok

Reasoning · Tool calling · Vision

Provider-specific limits and support can differ.

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Models to compare

Candidates match reported specifications; they are not tested replacements.

grok-4-1-fast-reasoningxAI · 2M contextCompare →Grok 4.20xAI · 2M contextCompare →Grok 4.20 Multi-AgentxAI · 2M contextCompare →

Model and price history

Price history (88 observations)

Date	Provider	Input / output
2026-11-03	Helicone	$0.20 / $0.50
2026-11-03	Jiekou.AI	$0.18 / $0.45
2026-11-03	302.AI	$0.20 / $0.50
2026-11-03	Poe	$0.20 / $0.50
2026-11-02	302.AI	$0.20 / $0.50
2026-11-02	Jiekou.AI	$0.18 / $0.45
2026-11-02	Helicone	$0.20 / $0.50
2026-11-02	Poe	$0.20 / $0.50
2026-11-01	Jiekou.AI	$0.18 / $0.45
2026-11-01	Helicone	$0.20 / $0.50
2026-11-01	Poe	$0.20 / $0.50
2026-11-01	302.AI	$0.20 / $0.50
2026-10-31	Poe	$0.20 / $0.50
2026-10-31	Jiekou.AI	$0.18 / $0.45
2026-10-31	302.AI	$0.20 / $0.50
2026-10-31	Helicone	$0.20 / $0.50
2026-10-30	Helicone	$0.20 / $0.50
2026-10-30	302.AI	$0.20 / $0.50
2026-10-30	Poe	$0.20 / $0.50
2026-10-30	Jiekou.AI	$0.18 / $0.45
2026-10-29	302.AI	$0.20 / $0.50
2026-10-29	Jiekou.AI	$0.18 / $0.45
2026-10-29	Poe	$0.20 / $0.50
2026-10-29	Helicone	$0.20 / $0.50
2026-10-28	Poe	$0.20 / $0.50
2026-10-28	302.AI	$0.20 / $0.50
2026-10-28	Helicone	$0.20 / $0.50
2026-10-28	Jiekou.AI	$0.18 / $0.45
2026-10-27	302.AI	$0.20 / $0.50
2026-10-27	Helicone	$0.20 / $0.50
2026-10-27	Jiekou.AI	$0.18 / $0.45
2026-10-27	Poe	$0.20 / $0.50
2026-10-27	Poe	$0.20 / $0.50
2026-10-27	302.AI	$0.20 / $0.50
2026-10-27	Jiekou.AI	$0.18 / $0.45
2026-10-27	Helicone	$0.20 / $0.50
2026-10-27	302.AI	$0.20 / $0.50
2026-10-27	Poe	$0.20 / $0.50
2026-10-27	Jiekou.AI	$0.18 / $0.45
2026-10-27	Helicone	$0.20 / $0.50
2026-10-27	302.AI	$0.20 / $0.50
2026-10-27	Helicone	$0.20 / $0.50
2026-10-27	Jiekou.AI	$0.18 / $0.45
2026-10-27	Poe	$0.20 / $0.50
2026-10-26	Jiekou.AI	$0.18 / $0.45
2026-10-26	302.AI	$0.20 / $0.50
2026-10-26	Poe	$0.20 / $0.50
2026-10-26	Helicone	$0.20 / $0.50
2026-10-25	302.AI	$0.20 / $0.50
2026-10-25	Helicone	$0.20 / $0.50
2026-10-25	Poe	$0.20 / $0.50
2026-10-25	Jiekou.AI	$0.18 / $0.45
2026-10-24	Helicone	$0.20 / $0.50
2026-10-24	Poe	$0.20 / $0.50
2026-10-24	Jiekou.AI	$0.18 / $0.45
2026-10-24	302.AI	$0.20 / $0.50
2026-10-24	Jiekou.AI	$0.18 / $0.45
2026-10-24	Helicone	$0.20 / $0.50
2026-10-24	Poe	$0.20 / $0.50
2026-10-24	302.AI	$0.20 / $0.50
2026-10-24	302.AI	$0.20 / $0.50
2026-10-24	Jiekou.AI	$0.18 / $0.45
2026-10-24	Poe	$0.20 / $0.50
2026-10-24	Helicone	$0.20 / $0.50
2026-10-23	Jiekou.AI	$0.18 / $0.45
2026-10-23	302.AI	$0.20 / $0.50
2026-10-23	Helicone	$0.20 / $0.50
2026-10-23	Poe	$0.20 / $0.50
2026-10-23	Jiekou.AI	$0.18 / $0.45
2026-10-23	302.AI	$0.20 / $0.50
2026-10-23	Helicone	$0.20 / $0.50
2026-10-23	Poe	$0.20 / $0.50
2026-10-23	Helicone	$0.20 / $0.50
2026-10-23	Jiekou.AI	$0.18 / $0.45
2026-10-23	302.AI	$0.20 / $0.50
2026-10-23	Poe	$0.20 / $0.50
2026-10-23	Poe	$0.20 / $0.50
2026-10-23	Jiekou.AI	$0.18 / $0.45
2026-10-23	Helicone	$0.20 / $0.50
2026-10-23	302.AI	$0.20 / $0.50
2026-10-23	Poe	$0.20 / $0.50
2026-10-23	Jiekou.AI	$0.18 / $0.45
2026-10-23	302.AI	$0.20 / $0.50
2026-10-23	Helicone	$0.20 / $0.50
2026-10-22	302.AI	$0.20 / $0.50
2026-10-22	Poe	$0.20 / $0.50
2026-10-22	Helicone	$0.20 / $0.50
2026-10-22	Jiekou.AI	$0.18 / $0.45