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Model comparison

Claude Opus 4.5 vs Grok Code Fast 1

Data verified

Head-to-head evidence from 12 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

64.22/100
Margin
25.6pts
← winning
38.64/100
1 category wins0 category wins

Public leaderboard positions: Claude Opus 4.5 #34 (Supported); Grok Code Fast 1 #180 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Opus 4.5 and Grok Code Fast 1 share 12 comparable benchmark results. 1 of 8 categories are comparable. 47 results are unique to Claude Opus 4.5; 0 to Grok Code Fast 1.

Updated July 20, 2026
Shared results
12
Claude Opus 4.5 only
47
Grok Code Fast 1 only
0
Comparable categories
1 / 8

Pick Claude Opus 4.5 if you want the stronger benchmark profile. Grok Code Fast 1 only becomes the better choice if you want the cheaper token bill or you need the larger 256K context window.

Confidence note. This is a partial-evidence comparison with 12 shared benchmark results across 5 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

Claude Opus 4.5 is clearly ahead on the BenchAlign aggregate, 64.22 to 38.64. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Opus 4.5's sharpest advantage is in coding, where it averages 71.7 against 70.8. The single biggest benchmark swing on the page is SWE-bench Verified, 80.9% to 70.8%.

Claude Opus 4.5 is also the more expensive model on tokens at $5.00 input / $25.00 output per 1M tokens, versus $0.20 input / $1.50 output per 1M tokens for Grok Code Fast 1. That is roughly 16.7x on output cost alone. Grok Code Fast 1 gives you the larger context window at 256K, compared with 200K for Claude Opus 4.5.

Category breakdown

Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.

Category scores and score margins for Claude Opus 4.5 and Grok Code Fast 1
CategoryClaude Opus 4.5ΔGrok Code Fast 1
CodingClaude Opus 4.571.7Margin← 0.9Grok Code Fast 170.8
AgenticClaude Opus 4.562.6MarginNo overlapGrok Code Fast 1Not measured
ReasoningClaude Opus 4.564.4MarginNo overlapGrok Code Fast 1Not measured
KnowledgeClaude Opus 4.558.1MarginNo overlapGrok Code Fast 1Not measured
MathClaude Opus 4.557.5MarginNo overlapGrok Code Fast 1Not measured
MultilingualClaude Opus 4.585.7MarginNo overlapGrok Code Fast 1Not measured
MultimodalClaude Opus 4.569.9MarginNo overlapGrok Code Fast 1Not measured
Inst. FollowingClaude Opus 4.569.5MarginNo overlapGrok Code Fast 1Not measured

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

More
A · Claude Opus 4.5B · Grok Code Fast 1

  1. SWE-bench Verified

    Coding
    Source ↗
    A 80.9%B 70.8%
    Winner: Claude Opus 4.5Δ 10.1
    SWE-bench Verified: Claude Opus 4.5 scored 80.9%; Grok Code Fast 1 scored 70.8%. Claude Opus 4.5 wins this benchmark.

Operational comparison

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

MetricClaude Opus 4.5Grok Code Fast 1Comparison
Input / output priceUSD per 1M tokensClaude Opus 4.5$5 input / $25 outputGrok Code Fast 1$0.2 input / $1.5 outputGrok Code Fast 1 has the lower combined listed price.
Generation speedtokens per secondClaude Opus 4.546 tok/sGrok Code Fast 1172 tok/sGrok Code Fast 1 has the higher measured throughput.
First-answer latencyseconds to first tokenClaude Opus 4.51.01 sGrok Code Fast 12.81 sClaude Opus 4.5 reaches the first token sooner.
Context windowmaximum listed tokensClaude Opus 4.5200KGrok Code Fast 1256KGrok Code Fast 1 lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
Terminal-Bench 2.0Source 59.3%—Not comparable
OSWorld-VerifiedSource 66.3%—Not comparable
OSWorldSource 66.3%—Not comparable
Claw-EvalSource 59.6%—Not comparable
QwenClawBenchSource 52.3%—Not comparable
τ³-bench resultsSource 70.2%—Not comparable
VITA-BenchSource 23.3%—Not comparable
DeepPlanningSource 26.4%—Not comparable
ToolathlonSource 43.5%—Not comparable
MCP AtlasSource 42.3%—Not comparable
MCP-TasksSource 71.8%—Not comparable
WideResearchSource 76.4%—Not comparable
CyberGymSource 50.6%—Not comparable
τ²-bench resultsSource 86.3%75.7%Claude Opus 4.5 leads
Gert LabsSource 64.23%—Not comparable
JobBenchSource 32.3%—Not comparable
CodingClaude Opus 4.5 wins
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
SWE-bench VerifiedSource 80.9%70.8%Claude Opus 4.5 leads
LiveCodeBench v6Source 84.8%—Not comparable
SWE-bench ProSource 57.1%—Not comparable
SWE MultilingualSource 77.5%—Not comparable
NL2RepoSource 43.2%—Not comparable
AA-SciCodeSource 47.0%36.2%Claude Opus 4.5 leads
Reasoning
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
LongBench v2Source 64.4%—Not comparable
AI-NeedleSource 74%—Not comparable
AA-LCRSource 65.3%48.3%Claude Opus 4.5 leads
CritPtSource 0.3%0.0%Claude Opus 4.5 leads
Knowledge
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
GPQASource 87%—Not comparable
SuperGPQASource 70.6%—Not comparable
MMLU-ProSource 89.5%—Not comparable
MMLU-ReduxSource 96.6%—Not comparable
C-EvalSource 92.2%—Not comparable
HLESource 30.8%—Not comparable
Artificial Analysis Intelligence IndexSource 34.7%21.6%Claude Opus 4.5 leads
AA-GPQA DiamondSource 81.0%72.7%Claude Opus 4.5 leads
AA-HLESource 12.9%7.5%Claude Opus 4.5 leads
AA-Omniscience IndexSource -3.9%-36.0%Claude Opus 4.5 leads
AA-Omniscience AccuracySource 40.7%23.8%Claude Opus 4.5 leads
AA-Omniscience Hallucination RateSource 75.4%78.5%Claude Opus 4.5 leads
AA MMLU-ProSource 88.9%—Not comparable
Math
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
AIME26Source 95.1%—Not comparable
HMMT Feb 2025Source 92.9%—Not comparable
HMMT Nov 2025Source 93.3%—Not comparable
HMMT Feb 2026Source 85.3%—Not comparable
MMAnswerBenchSource 84.0%—Not comparable
FrontierMath v2 (Tiers 1-3)Source 20.690%—Not comparable
FrontierMath v2 (Tier 4)Source 4.167%—Not comparable
Multilingual
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
MMLU-ProXSource 85.7%—Not comparable
NOVA-63Source 56.7%—Not comparable
Multimodal
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
MMMU-ProSource 70.6%—Not comparable
MathVisionSource 74.3%—Not comparable
CharXivSource 68.5%—Not comparable
VideoMMMUSource 84.4%—Not comparable
ScreenSpot ProSource 45.7%—Not comparable
V*Source 67.0%—Not comparable
AA-MMMU-ProSource 71.2%—Not comparable
Design Arena WebsiteSource 1279—Not comparable
Inst. Following
BenchmarkClaude Opus 4.5Grok Code Fast 1Result
IFEvalSource 90.9%—Not comparable
IFBenchSource 58%—Not comparable
AA-IFBenchSource 43.0%41.4%Claude Opus 4.5 leads
Frequently Asked Questions (2)

Which is better, Claude Opus 4.5 or Grok Code Fast 1?

Claude Opus 4.5 is ahead on BenchLM's BenchAlign leaderboard, 64.22 to 38.64. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 80.9% and 70.8%.

Which is better for coding, Claude Opus 4.5 or Grok Code Fast 1?

Claude Opus 4.5 has the edge for coding in this comparison, averaging 71.7 versus 70.8. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.

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