Model Comparison
Step 3.5 Flash 2603
vs. Step 3.7 Flash
Comparing 2 AI models · 7 benchmarks · StepFun
Recommended Pick
St Step 3.7 Flash 9 metric wins Strongest on: TTFT, Latency, Intelligence
Best Value
Step 3.5 Flash 2603
100.0 value score
47.9 reasoning / $0.15/1M
Lowest Price
Step 3.5 Flash 2603
$0.10/1M input price
Best Reasoning
Step 3.5 Flash 2603
47.9 reasoning score
Blends available reasoning benchmarks
Best for Coding
Step 3.7 Flash
37.1 coding index
Composite Indices
Higher is better; speed and price are normalized
Standard Benchmarks
Only benchmarks with data are shown
Differences That Matter
Best value
Step 3.5 Flash 2603 has the strongest quality-to-price mix at 100.0 out of 100 value points.
Price gap
Step 3.5 Flash 2603 is 2.0x cheaper on input tokens than Step 3.7 Flash.
Speed gap
Step 3.5 Flash 2603 generates about 1.3x as many tokens per second as Step 3.7 Flash.
Reasoning gap
Step 3.5 Flash 2603 leads Step 3.7 Flash by 0.1 points on reasoning.
Coding gap
Step 3.7 Flash leads Step 3.5 Flash 2603 by 2.5 points on coding.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
Step 3.5 Flash 2603
StepFun
TTFT
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Time
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tok/s
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Tokens
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Cost
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Step 3.7 Flash
StepFun
TTFT
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Time
—
tok/s
—
Tokens
—
Cost
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Which answer was more useful?
Full Comparison
| Metric | St Step 3.5 Flash 2603 | Top Pick St Step 3.7 Flash |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | $0.10/1M | $0.20/1M |
| Output Cost | $0.30/1M | $1.15/1M |
| Blended (3:1) | $0.15/1M | $0.44/1M |
| Specifications | ||
| Organization | StepFun | StepFun |
| Release Date | Apr 2, 2026 | May 29, 2026 |
| Performance & Speed | ||
| Throughput | 189.0 tok/s | 143.1 tok/s |
| TTFT | 6093ms | 1480ms |
| Latency | 16676ms | 15452ms |
| Composite Indices | ||
| Value Score | 100.0 | 34.2 |
| Reasoning Score | 47.9 | 47.8 |
| Intelligence | 38.5 | 42.6 |
| Coding | 34.6 | 37.1 |
| Standard Benchmarks | ||
| GPQA | 82.6% | 80.9% |
| HLE | 22.6% | 19.9% |
| SciCode | 38.5% | 40.0% |
| LCR | 54.3% | 63.7% |
| IFBench | 66.5% | 67.3% |
| TAU-bench v2 | 87.4% | 98.5% |
| TerminalBench Hard | 32.6% | 35.6% |
Key Takeaways
Step 3.5 Flash 2603 offers the best value at $0.10/1M, making it ideal for high-volume applications and cost-conscious projects.
Step 3.5 Flash 2603 has the strongest reasoning profile with a 47.9 reasoning score, combining the available reasoning-heavy benchmarks.
Step 3.7 Flash reaches a 37.1 coding index, making it the top choice for software development and code generation tasks.
All models support context windows of ∞+ tokens, suitable for processing lengthy documents and maintaining extended conversations.
When to Choose Each Model
Step 3.5 Flash 2603
- Cost-sensitive applications
- High-volume processing
- Complex reasoning tasks
- Research & analysis
Step 3.7 Flash
- Code generation
- Software development
