Model Comparison
Solar Pro 2 (Reasoning)
vs. Step 3.7 Flash
Comparing 2 AI models · 12 benchmarks · Upstage, StepFun
Recommended Pick
St Step 3.7 Flash 10 metric wins Strongest on: Throughput, Intelligence, Coding
Lowest Price
Solar Pro 2 (Reasoning)
$0.00/1M input price
Best Reasoning
Solar Pro 2 (Reasoning)
54.1 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
Price gap
Solar Pro 2 (Reasoning) is ∞x cheaper on input tokens than Step 3.7 Flash.
Reasoning gap
Solar Pro 2 (Reasoning) leads Step 3.7 Flash by 6.3 points on reasoning.
Coding gap
Step 3.7 Flash leads Solar Pro 2 (Reasoning) by 25.0 points on coding.
Top-pick rationale
Step 3.7 Flash wins 10 measurable categories, including Throughput, Intelligence, Coding, GPQA.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
Solar Pro 2 (Reasoning)
Upstage
TTFT
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Time
—
tok/s
—
Tokens
—
Cost
—
Step 3.7 Flash
StepFun
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Which answer was more useful?
Full Comparison
| Metric | Up Solar Pro 2 (Reasoning) | Top Pick St Step 3.7 Flash |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | $0.00/1M | $0.20/1M |
| Output Cost | $0.00/1M | $1.15/1M |
| Blended (3:1) | — | $0.44/1M |
| Specifications | ||
| Organization | Upstage | StepFun |
| Release Date | Jul 9, 2025 | May 29, 2026 |
| Performance & Speed | ||
| Throughput | — | 371.9 tok/s |
| TTFT | — | 767ms |
| Latency | — | 6145ms |
| Composite Indices | ||
| Value Score | — | 100.0 |
| Reasoning Score | 54.1 | 47.8 |
| Intelligence | 14.9 | 42.6 |
| Coding | 12.1 | 37.1 |
| Math | 61.3 | — |
| Standard Benchmarks | ||
| GPQA | 68.7% | 80.9% |
| MMLU Pro | 80.5% | — |
| HLE | 7.0% | 19.9% |
| LiveCodeBench | 61.6% | — |
| MATH 500 | 96.7% | — |
| AIME 2025 | 61.3% | — |
| AIME (Original) | 69.0% | — |
| SciCode | 30.2% | 40.0% |
| LCR | 0.0% | 63.7% |
| IFBench | 37.1% | 67.3% |
| TAU-bench v2 | 28.1% | 98.5% |
| TerminalBench Hard | 3.0% | 35.6% |
Key Takeaways
Solar Pro 2 (Reasoning) offers the best value at $0.00/1M, making it ideal for high-volume applications and cost-conscious projects.
Solar Pro 2 (Reasoning) has the strongest reasoning profile with a 54.1 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
Solar Pro 2 (Reasoning)
- Cost-sensitive applications
- High-volume processing
- Complex reasoning tasks
- Research & analysis
Step 3.7 Flash
- Code generation
- Software development
