Model Comparison
Qwen3 VL 4B (Reasoning)
vs. Step 3.5 Flash 2603
Comparing 2 AI models · 10 benchmarks · Alibaba, StepFun
Recommended Pick
St Step 3.5 Flash 2603 11 metric wins Strongest on: Throughput, Reasoning, Intelligence
Lowest Price
Qwen3 VL 4B (Reasoning)
$0.00/1M input price
Best Reasoning
Step 3.5 Flash 2603
47.9 reasoning score
Blends available reasoning benchmarks
Best for Coding
Step 3.5 Flash 2603
34.6 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
Qwen3 VL 4B (Reasoning) is ∞x cheaper on input tokens than Step 3.5 Flash 2603.
Reasoning gap
Step 3.5 Flash 2603 leads Qwen3 VL 4B (Reasoning) by 24.1 points on reasoning.
Coding gap
Step 3.5 Flash 2603 leads Qwen3 VL 4B (Reasoning) by 27.9 points on coding.
Top-pick rationale
Step 3.5 Flash 2603 wins 11 measurable categories, including Throughput, Reasoning, Intelligence, Coding.
Response Face-Off
Run one prompt through the selected models and compare response quality with live speed and cost context.
Qwen3 VL 4B (Reasoning)
Alibaba
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Step 3.5 Flash 2603
StepFun
TTFT
—
Time
—
tok/s
—
Tokens
—
Cost
—
Which answer was more useful?
Full Comparison
| Metric | Al Qwen3 VL 4B (Reasoning) | Top Pick St Step 3.5 Flash 2603 |
|---|---|---|
| Pricing per 1M tokens | ||
| Input Cost | $0.00/1M | $0.10/1M |
| Output Cost | $0.00/1M | $0.30/1M |
| Blended (3:1) | — | $0.15/1M |
| Specifications | ||
| Organization | Alibaba | StepFun |
| Release Date | Oct 14, 2025 | Apr 2, 2026 |
| Performance & Speed | ||
| Throughput | — | 198.7 tok/s |
| TTFT | — | 932ms |
| Latency | — | 10999ms |
| Composite Indices | ||
| Value Score | — | 100.0 |
| Reasoning Score | 23.8 | 47.9 |
| Intelligence | 13.7 | 38.5 |
| Coding | 6.7 | 34.6 |
| Math | 25.7 | — |
| Standard Benchmarks | ||
| GPQA | 49.4% | 82.6% |
| MMLU Pro | 70.0% | — |
| HLE | 4.4% | 22.6% |
| LiveCodeBench | 32.0% | — |
| AIME 2025 | 25.7% | — |
| SciCode | 17.1% | 38.5% |
| LCR | 21.3% | 54.3% |
| IFBench | 36.6% | 66.5% |
| TAU-bench v2 | 15.5% | 87.4% |
| TerminalBench Hard | 1.5% | 32.6% |
Key Takeaways
Qwen3 VL 4B (Reasoning) offers the best value at $0.00/1M, 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 3.5 Flash 2603 reaches a 34.6 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
Qwen3 VL 4B (Reasoning)
- Cost-sensitive applications
- High-volume processing
Step 3.5 Flash 2603
- Complex reasoning tasks
- Research & analysis
- Code generation
- Software development
