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Model comparison

Grok Code Fast 1 vs Qwen3.5 397B

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.

38.64/100
Margin
18.4pts
winning →
57.01/100
1 category wins0 category wins

Public leaderboard positions: Grok Code Fast 1 #180 (Supported); Qwen3.5 397B #71 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Grok Code Fast 1 and Qwen3.5 397B share 12 comparable benchmark results. 1 of 8 categories are comparable. 0 results are unique to Grok Code Fast 1; 43 to Qwen3.5 397B.

Updated July 22, 2026
Shared results
12
Grok Code Fast 1 only
0
Qwen3.5 397B only
43
Comparable categories
1 / 8

Pick Qwen3.5 397B if you want the stronger benchmark profile. Grok Code Fast 1 only becomes the better choice if coding is the priority or you want the cheaper token bill.

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

Qwen3.5 397B is clearly ahead on the BenchAlign aggregate, 57.01 to 38.64. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Qwen3.5 397B is also the more expensive model on tokens at $0.60 input / $3.60 output per 1M tokens, versus $0.20 input / $1.50 output per 1M tokens for Grok Code Fast 1. That is roughly 2.4x on output cost alone. Grok Code Fast 1 gives you the larger context window at 256K, compared with 128K for Qwen3.5 397B.

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 Grok Code Fast 1 and Qwen3.5 397B
CategoryGrok Code Fast 1ΔQwen3.5 397B
CodingGrok Code Fast 170.8Margin← 4.3Qwen3.5 397B66.5
AgenticGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B56.5
ReasoningGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B63.2
KnowledgeGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B56.6
MathGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B90.6
MultilingualGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B84.7
MultimodalGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B79.6
Inst. FollowingGrok Code Fast 1Not measuredMarginNo overlapQwen3.5 397B92.6

Decisive benchmark drivers

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

More
A · Grok Code Fast 1B · Qwen3.5 397B

  1. SWE-bench Verified

    Coding
    Source ↗
    A 70.8%B 76.2%
    Winner: Qwen3.5 397BΔ 5.4
    SWE-bench Verified: Grok Code Fast 1 scored 70.8%; Qwen3.5 397B scored 76.2%. Qwen3.5 397B wins this benchmark.

Operational comparison

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

MetricGrok Code Fast 1Qwen3.5 397BComparison
Input / output priceUSD per 1M tokensGrok Code Fast 1$0.2 input / $1.5 outputQwen3.5 397B$0.6 input / $3.6 outputGrok Code Fast 1 has the lower combined listed price.
Generation speedtokens per secondGrok Code Fast 1172 tok/sQwen3.5 397B96 tok/sGrok Code Fast 1 has the higher measured throughput.
First-answer latencyseconds to first tokenGrok Code Fast 12.81 sQwen3.5 397B2.44 sQwen3.5 397B reaches the first token sooner.
Context windowmaximum listed tokensGrok Code Fast 1256KQwen3.5 397B128KGrok Code Fast 1 lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
τ²-bench resultsSource 75.7%95.6%Qwen3.5 397B leads
Terminal-Bench 2.0Source —52.5%Not comparable
BrowseCompSource —62%Not comparable
Claw-EvalSource —56.8%Not comparable
QwenClawBenchSource —51.8%Not comparable
τ³-bench resultsSource —68.4%Not comparable
VITA-BenchSource —43.7%Not comparable
DeepPlanningSource —37.6%Not comparable
ToolathlonSource —36.3%Not comparable
MCP AtlasSource —46.1%Not comparable
MCP-TasksSource —74.2%Not comparable
WideResearchSource —74.0%Not comparable
Gert LabsSource —46.76%Not comparable
ResearchClawBenchSource —14.2%Not comparable
AA Agentic IndexSource —19.9%Not comparable
APEX-Agents-AASource —15.3%Not comparable
GDPval-AASource —23.1%Not comparable
GDPval-AASource —962Not comparable
CodingGrok Code Fast 1 wins
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
SWE-bench VerifiedSource 70.8%76.2%Qwen3.5 397B leads
AA-SciCodeSource 36.2%42.0%Qwen3.5 397B leads
LiveCodeBench v6Source —83.6%Not comparable
SWE-bench ProSource —50.9%Not comparable
AA Coding IndexSource —48.2%Not comparable
Reasoning
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
AA-LCRSource 48.3%65.7%Qwen3.5 397B leads
CritPtSource 0.0%1.7%Qwen3.5 397B leads
LongBench v2Source —63.2%Not comparable
AI-NeedleSource —68.7%Not comparable
Knowledge
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
Artificial Analysis Intelligence IndexSource 21.6%33.7%Qwen3.5 397B leads
AA-GPQA DiamondSource 72.7%89.3%Qwen3.5 397B leads
AA-HLESource 7.5%27.3%Qwen3.5 397B leads
AA-Omniscience IndexSource -36.0%-29.8%Qwen3.5 397B leads
AA-Omniscience AccuracySource 23.8%31.4%Qwen3.5 397B leads
AA-Omniscience Hallucination RateSource 78.5%89.1%Grok Code Fast 1 leads
GPQASource —88.4%Not comparable
SuperGPQASource —70.4%Not comparable
MMLU-ProSource —87.8%Not comparable
MMLU-ReduxSource —94.9%Not comparable
C-EvalSource —93%Not comparable
HLESource —28.7%Not comparable
Math
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
AIME26Source —93.3%Not comparable
HMMT Feb 2025Source —94.8%Not comparable
HMMT Nov 2025Source —92.7%Not comparable
HMMT Feb 2026Source —87.9%Not comparable
MMAnswerBenchSource —80.9%Not comparable
Multilingual
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
MMLU-ProXSource —84.7%Not comparable
NOVA-63Source —59.1%Not comparable
Multimodal
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
MMMU-ProSource —79%Not comparable
MathVisionSource —88.6%Not comparable
CharXivSource —80.8%Not comparable
VideoMMMUSource —84.7%Not comparable
ScreenSpot ProSource —65.6%Not comparable
V*Source —95.8%Not comparable
AA-MMMU-ProSource —77.3%Not comparable
Inst. Following
BenchmarkGrok Code Fast 1Qwen3.5 397BResult
AA-IFBenchSource 41.4%78.8%Qwen3.5 397B leads
IFEvalSource —92.6%Not comparable
Frequently Asked Questions (2)

Which is better, Grok Code Fast 1 or Qwen3.5 397B?

Qwen3.5 397B is ahead on BenchLM's BenchAlign leaderboard, 57.01 to 38.64. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 70.8% and 76.2%.

Which is better for coding, Grok Code Fast 1 or Qwen3.5 397B?

Grok Code Fast 1 has the edge for coding in this comparison, averaging 70.8 versus 66.5. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.

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