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Model comparison

GPT-5.1-Codex vs Step 3.7 Flash

Data verified

Head-to-head evidence from 15 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

52.62/100
Margin
1.9pts
← winning
50.76/100
0 category wins0 category wins

BenchAlign evidence: GPT-5.1-Codex estimated; Step 3.7 Flash estimated. Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. GPT-5.1-Codex and Step 3.7 Flash share 15 comparable benchmark results. 0 of 8 categories are comparable. 2 results are unique to GPT-5.1-Codex; 15 to Step 3.7 Flash.

Updated July 16, 2026
Shared results
15
GPT-5.1-Codex only
2
Step 3.7 Flash only
15
Comparable categories
0 / 8

Benchmark data for GPT-5.1-Codex and Step 3.7 Flash is coming soon on BenchLM.

Confidence note. This is a partial-evidence comparison with 15 shared benchmark results across 6 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.

GPT-5.1-Codex has the larger context window at 400K, compared with 256K for Step 3.7 Flash.

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 GPT-5.1-Codex and Step 3.7 Flash
CategoryGPT-5.1-CodexΔStep 3.7 Flash
AgenticGPT-5.1-CodexNot measuredMarginNo overlapStep 3.7 Flash66.4
CodingGPT-5.1-CodexNot measuredMarginNo overlapStep 3.7 Flash56.3

Operational comparison

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

MetricGPT-5.1-CodexStep 3.7 FlashComparison
Input / output priceUSD per 1M tokensGPT-5.1-CodexNot availableStep 3.7 Flash$0.2 input / $1.15 outputA complete price comparison is not available.
Generation speedtokens per secondGPT-5.1-CodexNot availableStep 3.7 FlashNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenGPT-5.1-CodexNot availableStep 3.7 FlashNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensGPT-5.1-Codex400KStep 3.7 Flash256KGPT-5.1-Codex lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
τ²-bench resultsSource 83%98.5%Step 3.7 Flash leads
Gert LabsSource 49.68%51.57%Step 3.7 Flash leads
JobBenchSource 26.2%Not comparable
Terminal-Bench 2.0Source 59.5%Not comparable
BrowseCompSource 75.8%Not comparable
DeepSearchQASource 92.8%Not comparable
GDPval-AASource 25.9%Not comparable
ToolathlonSource 49.5%Not comparable
Claw-EvalSource 67.1%Not comparable
HLE w/ toolsSource 47.2%Not comparable
AA Agentic IndexSource 21.5%Not comparable
GDPval-AASource 1017Not comparable
APEX-Agents-AASource 14.8%Not comparable
Coding
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
Vibe Code BenchSource 13.12%Not comparable
Terminal-Bench HardSource 34.8%35.6%Step 3.7 Flash leads
AA-SciCodeSource 40.2%40.0%GPT-5.1-Codex leads
SWE-bench ProSource 56.3%Not comparable
Terminal-Bench 2.0Source 59.5%Not comparable
AA Coding IndexSource 39.6%Not comparable
Reasoning
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
AA-LCRSource 67.3%63.7%GPT-5.1-Codex leads
CritPtSource 5.7%2.3%GPT-5.1-Codex leads
Knowledge
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
Artificial Analysis Intelligence IndexSource 34.7%30.3%GPT-5.1-Codex leads
AA-GPQA DiamondSource 86.0%80.9%GPT-5.1-Codex leads
AA-HLESource 23.4%19.9%GPT-5.1-Codex leads
AA-Omniscience IndexSource -6.0%-37.5%GPT-5.1-Codex leads
AA-Omniscience AccuracySource 39.2%25.4%GPT-5.1-Codex leads
AA-Omniscience Hallucination RateSource 74.4%84.4%GPT-5.1-Codex leads
Multimodal
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
AA-MMMU-ProSource 72.5%75.3%Step 3.7 Flash leads
Design Arena WebsiteSource 11951218Step 3.7 Flash leads
SimpleVQASource 79.2%Not comparable
V*Source 95.3%Not comparable
Inst. Following
BenchmarkGPT-5.1-CodexStep 3.7 FlashResult
AA-IFBenchSource 70.0%67.3%GPT-5.1-Codex leads
Frequently Asked Questions (3)

Can I compare GPT-5.1-Codex and Step 3.7 Flash 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 GPT-5.1-Codex and Step 3.7 Flash today?

Step 3.7 Flash: $0.20 input / $1.15 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 16, 2026

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