Claude Opus 4.5 vs Step-3.5-Flash: Specs & Benchmark Comparison
| Characteristic | Claude Opus 4.5 | Step-3.5-Flash |
|---|---|---|
| Company | Anthropic | StepFun |
| Release Date | November 23, 2025 | February 1, 2026 |
| Parameters | — | 196B |
| Multimodal | Yes | Yes |
| Context (input) | 200K | 66K |
| Context (output) | 64K | 8K |
| Input Price / 1M | $5.00 | $0.10 |
| Output Price / 1M | $25.00 | $0.40 |
| Average Score | 0.9 | 0.8 |
| Benchmarks | ||
| SWE-Bench Verified | 0.8 | 0.7 |
Visual Benchmark Comparison
Claude Opus 4.5
Step-3.5-Flash
SWE-Bench Verified0.8 vs 0.7
0.8
0.7
Verdict
Step-3.5-Flash leads in 2 out of 5 comparison categories.
Overall Performance
Both models show comparable average scores: Claude Opus 4.5 — 0.9, Step-3.5-Flash — 0.8.
Programming
On SWE-Bench, both models are nearly equal: Claude Opus 4.5 — 0.8, Step-3.5-Flash — 0.7.
API Cost
Step-3.5-Flash is 60.0x cheaper: input $0.10/1M vs $5.00/1M tokens.
Context Window
Claude Opus 4.5 supports a larger context: 200K vs 66K tokens.
Recency
Step-3.5-Flash is newer: released 2/1/2026 vs 11/23/2025.
More About These Models
Related Comparisons
The Claude Opus 4.5 and Step-3.5-Flash comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Opus 4.5 or Step-3.5-Flash page. See also the complete list of AI model comparisons.