# Claude Opus 4.5 vs Step 3.7 Flash

> Side-by-side benchmark comparison for Claude Opus 4.5 and Step 3.7 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-4-5-vs-step-3-7-flash
- Last updated: October 15, 2026

- Shared sourced benchmarks: 6
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Claude Opus 4.5 leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Claude Opus 4.5 has the higher overall point estimate 54.01 to 43.7. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in instruction following, where the averages are 31.9 for Claude Opus 4.5 and 82.1 for Step 3.7 Flash.
- The biggest single benchmark swing is V* in Multimodal & Grounded, with scores of 67.0% and 95.3%.
- Step 3.7 Flash is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Step 3.7 Flash also has the larger context window at 256K.

## Model Snapshot

| Property | Claude Opus 4.5 | Step 3.7 Flash |
|----------|----------|----------|
| Creator | Anthropic | StepFun |
| Type | Proprietary | Open Weight |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 200K | 256K |
| Overall Score | 54.01 | 43.7 |
| Benchmarks Covered | 61 | 11 |
| Pricing (input/output) | $5.00 / $25.00 | $0.20 / $1.15 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Claude Opus 4.5 public-lane score: 32.4 (Estimated · #87/126)
- Step 3.7 Flash public-lane score: 37.1 (Estimated · #74/126)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 59.3% | Coming soon | Coming soon |
| OSWorld-Verified | 66.3% | Coming soon | Coming soon |
| OSWorld | 66.3% | Coming soon | Coming soon |
| Claw-Eval | 59.6% | 67.1% | Step 3.7 Flash |
| QwenClawBench | 52.3% | Coming soon | Coming soon |
| τ³-bench results | 70.2% | Coming soon | Coming soon |
| VITA-Bench | 23.3% | Coming soon | Coming soon |
| DeepPlanning | 26.4% | Coming soon | Coming soon |
| Toolathlon | 43.5% | 49.5% | Step 3.7 Flash |
| MCP Atlas | 42.3% | Coming soon | Coming soon |
| MCP-Tasks | 71.8% | Coming soon | Coming soon |
| WideResearch | 76.4% | Coming soon | Coming soon |
| CyberGym | 50.6% | Coming soon | Coming soon |
| Gert Labs | 64.23% | 51.57% | Claude Opus 4.5 |
| JobBench | 32.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 59.5% | Coming soon |
| BrowseComp | Coming soon | 75.8% | Coming soon |
| DeepSearchQA | Coming soon | 92.8% | Coming soon |
| HLE w/ tools | Coming soon | 47.2% | Coming soon |

### Coding

- Winner: Directional only
- Claude Opus 4.5 public-lane score: 40.4 (Estimated · #64/149)
- Step 3.7 Flash public-lane score: 30.2 (Estimated · #95/149)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 80.9% | Coming soon | Coming soon |
| LiveCodeBench v6 | 84.8% | Coming soon | Coming soon |
| SWE-bench Pro | 57.1% | 56.3% | Claude Opus 4.5 |
| SWE Multilingual | 77.5% | Coming soon | Coming soon |
| NL2Repo | 43.2% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 59.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 59.5% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 78.3 (Unranked · 4 rankable rows)
- Step 3.7 Flash public-lane score: 76.5 (Unranked · 2 rankable rows)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| LongBench v2 | 64.4% | Coming soon | Coming soon |
| AI-Needle | 74% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 48.6 (#49/54)
- Step 3.7 Flash public-lane score: 75.4 (Unranked · 3 rankable rows)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| MMMU | 80.7% | Coming soon | Coming soon |
| MMMU-Pro | 70.6% | Coming soon | Coming soon |
| RealWorldQA | 77.0% | Coming soon | Coming soon |
| OmniDocBench 1.5 | 87.7% | Coming soon | Coming soon |
| Video-MME (with subtitle) | 77.6% | Coming soon | Coming soon |
| Video-MME (w/o subtitle) | 81.4% | Coming soon | Coming soon |
| MathVision | 74.3% | Coming soon | Coming soon |
| We-Math | 70.0% | Coming soon | Coming soon |
| DynaMath | 79.7% | Coming soon | Coming soon |
| SimpleVQA | 65.7% | 79.2% | Step 3.7 Flash |
| CharXiv | 68.5% | Coming soon | Coming soon |
| CountBench | 90.6% | Coming soon | Coming soon |
| AI2D_TEST | 87.7% | Coming soon | Coming soon |
| ERQA | 46.8% | Coming soon | Coming soon |
| VideoMMMU | 84.4% | Coming soon | Coming soon |
| MLVU (M-Avg) | 81.7% | Coming soon | Coming soon |
| ScreenSpot Pro | 45.7% | Coming soon | Coming soon |
| V* | 67.0% | 95.3% | Step 3.7 Flash |

### Knowledge

- Winner: Directional only
- Claude Opus 4.5 public-lane score: 51.1 (Estimated · #76/182)
- Step 3.7 Flash public-lane score: 45 (Estimated · #96/182)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 87% | Coming soon | Coming soon |
| SuperGPQA | 70.6% | Coming soon | Coming soon |
| MMLU-Pro | 89.5% | Coming soon | Coming soon |
| MMLU-Redux | 96.6% | Coming soon | Coming soon |
| C-Eval | 92.2% | Coming soon | Coming soon |
| HLE | 30.8% | Coming soon | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 96.5 (#2/17)
- Step 3.7 Flash public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| MMLU-ProX | 85.7% | Coming soon | Coming soon |
| NOVA-63 | 56.7% | Coming soon | Coming soon |
| INCLUDE | 86.2% | Coming soon | Coming soon |
| PolyMath | 79.0% | Coming soon | Coming soon |
| MAXIFE | 79.2% | Coming soon | Coming soon |

### Instruction Following

- Winner: Directional only
- Claude Opus 4.5 public-lane score: 31.9 (#129/146)
- Step 3.7 Flash public-lane score: 82.1 (#54/146)

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 90.9% | Coming soon | Coming soon |
| IFBench | 58% | Coming soon | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 61.3 (#9/12)
- Step 3.7 Flash public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Step 3.7 Flash | Winner |
|-----------|-----------|-----------|--------|
| AIME26 | 95.1% | Coming soon | Coming soon |
| HMMT Feb 2025 | 92.9% | Coming soon | Coming soon |
| HMMT Nov 2025 | 93.3% | Coming soon | Coming soon |
| HMMT Feb 2026 | 85.3% | Coming soon | Coming soon |
| MMAnswerBench | 84.0% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 34.386% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 4.878% | Coming soon | Coming soon |

## FAQ

### Which is better overall, Claude Opus 4.5 or Step 3.7 Flash?

Claude Opus 4.5 has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between Claude Opus 4.5 and Step 3.7 Flash?

The widest category gap is in instruction following, where the averages are 31.9 for Claude Opus 4.5 and 82.1 for Step 3.7 Flash.

### How many benchmarks does Claude Opus 4.5 cover on BenchLM?

Claude Opus 4.5 currently has 61 sourced benchmark scores on BenchLM.

### How many benchmarks does Step 3.7 Flash cover on BenchLM?

Step 3.7 Flash currently has 11 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Opus 4.5 vs Claude Opus 4.5 Thinking](/compare/claude-opus-4-5-vs-claude-opus-4-5-thinking)
- [Step 3.7 Flash vs Claude Opus 4.5 Thinking](/compare/claude-opus-4-5-thinking-vs-step-3-7-flash)
- [Claude Opus 4.5 vs Claude Opus 5.5](/compare/claude-opus-4-5-vs-claude-opus-5-5)
- [Step 3.7 Flash vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-step-3-7-flash)

## Explore More

- [Claude Opus 4.5 profile](/models/claude-opus-4-5)
- [Step 3.7 Flash profile](/models/step-3-7-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)