Model Comparison
Solar Open2 250B
vs. Step 3.5 Flash 2603
Comparing 2 AI models · 0 benchmarks · Upstage, StepFun
Recommended Pick
UpSolar Open2 250B2 metric winsStrongest on: Reasoning, Intelligence
Lowest Price
Step 3.5 Flash 2603
$0.10/1M input price
Best Reasoning
Solar Open2 250B
24.7 reasoning score
Blends available reasoning benchmarks
Best for Coding
Solar Open2 250B
45.0 coding index
Differences That Matter
Reasoning gap
Solar Open2 250B leads Step 3.5 Flash 2603 by 7.7 points on reasoning.
Top-pick rationale
Solar Open2 250B wins 2 measurable categories, including Reasoning, Intelligence.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
Solar Open2 250B
Upstage
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 3.5 Flash 2603
StepFun
TTFT
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Time
—
tok/s
—
Tokens
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Cost
—
Which answer was more useful?
Secure AI Chat made in Europe
Use Claude, ChatGPT, Gemini alongside with EU-Hosted Models like Deepseek, Qwen & Kimi.
EU-hosted inference
Servers in Germany & Finland. Designed to meet strict GDPR and ISO 27001 compliance requirements.
Full Comparison
| Metric | Top Pick Up Solar Open2 250B | St Step 3.5 Flash 2603 |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | — | $0.10/1M |
| Output Cost | — | $0.30/1M |
| Blended (3:1) | — | $0.15/1M |
| Specifications | ||
| Organization | Upstage | StepFun |
| Release Date | Aug 12, 2026 | Apr 2, 2026 |
| Performance & Speed | ||
| Throughput | — | 145.8 tok/s |
| TTFT | — | 3370ms |
| Latency | — | 17090ms |
| Composite Indices | ||
| Value Score | — | 100.0 |
| Reasoning Score | 24.7 | 17.0 |
| Intelligence | 24.7 | 17.0 |
| Coding | 45.0 | — |
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.
Solar Open2 250B has the strongest reasoning profile with a 24.7 reasoning score,combining the available reasoning-heavy benchmarks.
Solar Open2 250B reaches a 45.0 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 Open2 250B
- Complex reasoning tasks
- Research & analysis
- Code generation
- Software development
Step 3.5 Flash 2603
- Cost-sensitive applications
- High-volume processing
