GPT-5.1 Codex vs Step 3.7 Flash
Side-by-side benchmark comparison across coding, math, reasoning, speed, and pricing.
Step 3.7 Flash by StepFun wins on 5 of 7 benchmarks against GPT-5.1 Codex by OpenAI, which leads on 2. This head-to-head comparison covers coding, math, reasoning, speed, and pricing metrics from our benchmark data.
Category-by-Category Breakdown
Coding: In coding, GPT-5.1 Codex scores 1197 on Design Arena ELO compared to Step 3.7 Flash's 1172, while Step 3.7 Flash scores 1206 on Website Arena ELO compared to GPT-5.1 Codex's 1174.
Reasoning: In reasoning, Step 3.7 Flash scores 76.6% on GPQA Diamond compared to GPT-5.1 Codex's 65.0%.
Context: In context, GPT-5.1 Codex scores 400K on Context Length compared to Step 3.7 Flash's 262K.
Pricing Comparison
GPT-5.1 Codex costs $1.3/1M input tokens and $10.0/1M output tokens, while Step 3.7 Flash costs $0.20/1M input and $1.1/1M output. Step 3.7 Flash is the more affordable option for API usage.
Verdict
Step 3.7 Flash leads across the board in affordability, making it the stronger overall choice in this comparison.
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GPT-5.1 Codex vs Step 3.7 Flash — FAQ
Which is better, GPT-5.1 Codex or Step 3.7 Flash?
Step 3.7 Flash wins on more benchmarks overall (5 vs 2). However, the best choice depends on your specific needs — each model excels in different areas.
How does GPT-5.1 Codex compare to Step 3.7 Flash for coding?
SWE-bench Verified data is not available for both models. Check the detailed comparison charts above for other coding-related metrics.
Is GPT-5.1 Codex cheaper than Step 3.7 Flash?
Yes, Step 3.7 Flash is cheaper. GPT-5.1 Codex costs $1.3/1M input and $10.0/1M output tokens. Step 3.7 Flash costs $0.20/1M input and $1.1/1M output tokens.
Which is faster, GPT-5.1 Codex or Step 3.7 Flash?
Output speed data is not available for both models. Check the speed section of the comparison above for available performance data.
What benchmarks does the GPT-5.1 Codex vs Step 3.7 Flash comparison cover?
This comparison covers 7 benchmarks including GPQA Diamond, Input Cost, Output Cost, Context Length, Cached Input Cost, Design Arena ELO, Website Arena ELO. Metrics span general intelligence, coding, math, reasoning, speed, and cost categories.