Grok 4.1 Fast (Reasoning)

Retired May 2026

Reasoning variant of Grok 4.1 Fast, released November 2025, built on unified weights shared with the non-reasoning variant and steered toward multi-step reasoning with fewer hallucinations.

Context: 2M tokens
Cutoff: Oct 2024
Released: Nov 2025

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Hosted API price

Cheapest via Azure · per 1M tokens

USD

Input: $0.20 /1M
Output: $0.50 /1M
Hosted by: 1 provider

Hosted API pricing

How we price

Order

Providers are listed cheapest input rate first, then by output rate, a tie going to the creator's own listing. A provider that lists the model without a published rate sits at the end.

Prices

Base-tier, on-demand rates in USD per 1M tokens, converted at ECB reference rates where a provider publishes in another currency. Cached-input and batch rates show only where a provider publishes them. "Cheapest" marks the one provider with the lowest input and output pair; a tie wears no badge.

Cost

Input rate times the input tokens plus output rate times the output tokens, at the monthly volume set above the table. Cached-input, batch, long-context and reasoning-token billing are not modelled.

Transparency and funding

Affiliates: Affiliate links are marked. We may earn a commission if you click them, but commissions never affect the order.

Every provider serving Grok 4.1 Fast (Reasoning), cheapest input first. Set your monthly volume to see what each would bill.

Input M Output M

Every provider serving Grok 4.1 Fast (Reasoning), with its price per 1M input and output tokens and what the volume above would cost
Provider	Input /1M	Output /1M	Cost at 10M in + 2M out	Link
Azure	$0.20	$0.50	$3.00	Visit website

Heads up: Base-tier, on-demand rates per 1M tokens; cached, batch and long-context tiers excluded. A provider may serve a shorter context or a quantized build than the creator's release. Verify before provisioning. More on how we price.

Similarly priced models

The models nearest Grok 4.1 Fast (Reasoning) by blended rate, each at its own cheapest provider.

Models priced nearest Grok 4.1 Fast (Reasoning) per 1M tokens, each at its cheapest provider
Model	Blended /1M	Input /1M	Output /1M	Context	Cutoff	vs Grok 4.1 Fast (Reasoning)
MiniMax-M2.7 MiniMax	$0.225	$0.15	$0.60	205K		−10%
Mistral Small 4 Mistral	$0.225	$0.15	$0.60	256K		−10%
Qwen3.8-27B Alibaba Cloud	$0.225	$0.17	$0.50	262K		−10%
Llama 4 Scout Meta	$0.24	$0.16	$0.64	10M	Aug 2024	−4%
Qwen3.5-122B-A10B Alibaba Cloud	$0.2487	$0.115	$0.917	262K		−1%
Grok 4.1 Fast (Reasoning) This model xAI	$0.25	$0.20	$0.50	2M	Oct 2024
Qwen3.8-Flash-Next Alibaba Cloud	$0.25	$0.20	$0.50	262K		0%
Qwen3-235B-A22B Instruct (2507) Alibaba Cloud	$0.2667	$0.20	$0.60	262K		+7%
Qwen3-VL-30B-A3B Instruct Alibaba Cloud	$0.2833	$0.20	$0.70	262K		+13%
Muse Glimmer 30B Meta	$0.30	$0.20	$0.80	131K	Jan 2026	+20%
Qwen2.5-7B Instruct Alibaba Cloud	$0.30	$0.30	$0.30	33K		+20%

USD per 1M tokens at each model's cheapest listed provider. Blended is the cost of 10M input plus 2M output tokens, spread over the 12M.

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Capabilities

What Grok 4.1 Fast (Reasoning) accepts and can do, as published by xAI.

Text Accepts and generates natural-language text.
Image Accepts images as input alongside text.
Reasoning Thinks before it answers, always on or as a switchable mode.
Function calling Connect to external tools, APIs, and systems.
Structured output Return responses in structured formats like JSON.

Common questions

What is Grok 4.1 Fast (Reasoning) good for?

Multi-step reasoning that suited agent loops and analysing long documents in one call. It took text and images, and xAI says it hallucinated less than the models before it.

When is Grok 4.1 Fast (Reasoning) not a good fit?

Any new work: xAI retired it in May 2026, and its migration guide points to Grok 4.3 with low reasoning effort. No built-in web search or code execution, and closed weights.

What is the cheapest way to run Grok 4.1 Fast (Reasoning)?

The cheapest hosted rate is $0.20 / $0.50 per 1M tokens via Azure.

How does Grok 4.1 Fast (Reasoning) compare with Grok 4 Fast (Reasoning)?

xAI says Grok 4.1 Fast (Reasoning) was trained with long-horizon reinforcement learning in simulated tool environments across dozens of domains, holds up better over long multi-turn agent runs, and hallucinates much less than Grok 4 Fast (Reasoning). It launched alongside xAI's Agent Tools API. Same 2M-token context and text and image input. Grok 4.1 Fast (Reasoning) came out 2 months later.

Can I self-host Grok 4.1 Fast (Reasoning)?

No. xAI does not publish the weights; Grok 4.1 Fast (Reasoning) is available only through hosted APIs.