Model Comparison
Solar Pro 3
vs. Step 3.5 Flash
Comparing 2 AI models · 0 benchmarks · Upstage, StepFun
Recommended Pick
StStep 3.5 Flash4 metric winsStrongest on: Input price, Output price, Blended price
Lowest Price
Step 3.5 Flash
$0.10/1M input price
Best for Coding
Solar Pro 3
16.2 coding index
Differences That Matter
Price gap
Step 3.5 Flash is 1.5x cheaper on input tokens than Solar Pro 3.
Speed gap
Step 3.5 Flash generates about 1.1x as many tokens per second as Solar Pro 3.
Top-pick rationale
Step 3.5 Flash wins 4 measurable categories, including Input price, Output price, Blended price, Throughput.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
Solar Pro 3
Upstage
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Step 3.5 Flash
StepFun
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Which answer was more useful?
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Full Comparison
| Metric | Up Solar Pro 3 | Top Pick St Step 3.5 Flash |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | $0.15/1M | $0.10/1M |
| Output Cost | $0.60/1M | $0.30/1M |
| Blended (3:1) | $0.26/1M | $0.15/1M |
| Specifications | ||
| Organization | Upstage | StepFun |
| Release Date | Apr 6, 2026 | Feb 2, 2026 |
| Performance & Speed | ||
| Throughput | 142.2 tok/s | 156.4 tok/s |
| TTFT | 1260ms | 3300ms |
| Latency | 15330ms | 16080ms |
| Composite Indices | ||
| Coding | 16.2 | — |
Key Takeaways
Step 3.5 Flash offers the best value at $0.10/1M,making it ideal for high-volume applications and cost-conscious projects.
Solar Pro 3 reaches a 16.2 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 3
- Code generation
- Software development
Step 3.5 Flash
- Cost-sensitive applications
- High-volume processing
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