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Grok 4.1 Fast Reasoning

Retired xAI model, slug grok-4-1-fast-reasoning.

text + image + file → text · made by xAI

$0.2$0.5per Mtok in / out
Microsoft Azure AI · 3 sellers

Sold by 5 ways

SellerLaneRate
Google Vertex AI 0 ways$0.2per Mtok in$0.5per Mtok out$0.05per Mtok cached
Google Vertex AI cloudnot on the seller's list todaystandard$0.2per Mtok in$0.5per Mtok out$0.05per Mtok cachedcloud.google.com · read 2026-08-24
Microsoft Azure AI cloudstandard$0.2per Mtok in$0.5per Mtok out$0.05per Mtok cachedmodels.dev · read 2026-09-16
Oracle Cloud Infrastructure 0 ways$5per Mtok in$25per Mtok out
Oracle Cloud Infrastructure cloudnot on the seller's list todaystandard$5per Mtok in$25per Mtok outraw.githubusercontent.com · read 2026-08-27
Requesty aggregatorxai$0.2per Mtok in$0.5per Mtok out$0.05per Mtok cachedrouter.requesty.ai · read 2026-08-28
Vercel AI Gateway aggregatorstandard$0.2per Mtok in$0.5per Mtok out$0.05per Mtok cachedai-gateway.vercel.sh · read 2026-08-25

Measured 14 standings

PlaceBoardMetricScore
5thof 109Berkeley Function-Calling Leaderboard (BFCL) V4Overall Acc (fc)69.57
16thof 81Forecastbench — Epoch AIOverall score61
20thof 32AIME 2026Accuracy (± 95% CI)94.17
21stof 61AIME 2025Accuracy (± 95% CI)89.17
38thof 161Dtbench — Epoch AIAccuracy87.73
41stof 102Simplebench — Epoch AIScore (AVG@5)0.56
45thof 60Vending bench 2 — Epoch AIScore1106.628
58thof 64Proofbench — Epoch AIAccuracy4
81stof 152LMArena · VisionScore (Elo)1195
96thof 112Ale bench — Epoch AIPerformance394.93
97thof 105Vectara Hallucination LeaderboardHallucination Rate19.2
101stof 402LMArena · TextScore (Elo)1430
117thof 128LMArena · WebDevScore (Elo)1240
117thof 121Webdev arena — Epoch AIArena Score1223

About

Grok 4.1 Fast Reasoning — a text model from xAI, sold by 3 companies from $0.2 in and $0.5 out per million tokens, placed 5th of 109 on Berkeley Function-Calling Leaderboard (BFCL) V4.

It takes text, images and files and returns text, with a context window of 1,000,000 tokens. It was published in November 2025. Its sellers say it can reason step by step and call a tool. The catalogue files it under reasoning, code and agents. Three companies sell it. The cheapest is $0.2 in and $0.5 out per million tokens at Microsoft Azure AI. Beside the standard rate there is a separately routed lane. It has been measured on 14 boards, and stands best at 5th of 109 on Berkeley Function-Calling Leaderboard (BFCL) V4.

Every current figure

Maker
xAI
Register
model
Takes
text + image + file
Returns
text
Context
1,000,000 tokens
Published
November 2025
Licence
not read
Sellers
3
Maker's own price
not read
Price
$0.2 in and $0.5 out per million tokens — Microsoft Azure AI
Boards
14
Best place
5th of 109 — Berkeley Function-Calling Leaderboard (BFCL) V4

Known as 5 names

Grok 4.1 Fast (Reasoning)Grok-4-1-fast-reasoning (FC)xai/grok-4-1-fast-reasoningspacexai/grok-4.1-fast-reasoningxai/grok-4.1-fast-reasoning