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Model comparison

Claude 3.5 Sonnet vs Grok 4.1 Fast

Data verified

Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

No sourced benchmark result is currently shared by both models. This page therefore compares only the available metadata, pricing, and runtime rows; it does not name a quality winner.
47.74/100
Margin
3.5pts
winning →
51.25/100
0 category wins0 category wins

Public leaderboard positions: Claude 3.5 Sonnet #132 (Estimated); Grok 4.1 Fast #107 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude 3.5 Sonnet and Grok 4.1 Fast share 0 comparable benchmark results. 0 of 8 categories are comparable. 4 results are unique to Claude 3.5 Sonnet; 13 to Grok 4.1 Fast.

Updated July 21, 2026
Shared results
0
Claude 3.5 Sonnet only
4
Grok 4.1 Fast only
13
Comparable categories
0 / 8

Benchmark data for Claude 3.5 Sonnet and Grok 4.1 Fast is coming soon on BenchLM.

Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.

Claude 3.5 Sonnet is priced at $3.00 input / $15.00 output per 1M tokens, versus $0.20 input / $0.50 output per 1M tokens for Grok 4.1 Fast. Grok 4.1 Fast has the larger context window at 1M, compared with 200K for Claude 3.5 Sonnet.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

MetricClaude 3.5 SonnetGrok 4.1 FastComparison
Input / output priceUSD per 1M tokensClaude 3.5 Sonnet$3 input / $15 outputGrok 4.1 Fast$0.2 input / $0.5 outputGrok 4.1 Fast has the lower combined listed price.
Generation speedtokens per secondClaude 3.5 SonnetNot availableGrok 4.1 Fast138 tok/sA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude 3.5 SonnetNot availableGrok 4.1 Fast0.54 sA complete latency comparison is not available.
Context windowmaximum listed tokensClaude 3.5 Sonnet200KGrok 4.1 Fast1MGrok 4.1 Fast lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
τ²-bench resultsSource 63.7%Not comparable
Gert LabsSource 47.32%Not comparable
Coding
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
SWE-bench VerifiedSource 49%Not comparable
AA-SciCodeSource 29.6%Not comparable
Reasoning
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
AA-LCRSource 22.0%Not comparable
CritPtSource 0.0%Not comparable
Knowledge
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
GPQASource 59.4%Not comparable
Artificial Analysis Intelligence IndexSource 16.9%Not comparable
AA-GPQA DiamondSource 63.7%Not comparable
AA-HLESource 5.0%Not comparable
AA-Omniscience IndexSource -50.9%Not comparable
AA-Omniscience AccuracySource 17.0%Not comparable
AA-Omniscience Hallucination RateSource 81.8%Not comparable
Math
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
FrontierMath v2 (Tiers 1-3)Source 2.069%Not comparable
FrontierMath v2 (Tier 4)Source 0.000%Not comparable
Multimodal
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
AA-MMMU-ProSource 48.4%Not comparable
Inst. Following
BenchmarkClaude 3.5 SonnetGrok 4.1 FastResult
AA-IFBenchSource 36.5%Not comparable
Frequently Asked Questions (3)

Can I compare Claude 3.5 Sonnet and Grok 4.1 Fast on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.

Why does this comparison show “coming soon”?

BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.

What data is available for Claude 3.5 Sonnet and Grok 4.1 Fast today?

Claude 3.5 Sonnet: $3.00 input / $15.00 output per 1M tokens Grok 4.1 Fast: $0.20 input / $0.50 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.

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Last updated: July 21, 2026

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