# o4-mini vs Step 3.5 Flash

> Side-by-side benchmark comparison for o4-mini and Step 3.5 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/o4-mini-vs-step-3-5-flash
- Last updated: October 23, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for o4-mini and Step 3.5 Flash.

## Summary

- o4-mini and Step 3.5 Flash do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | o4-mini | Step 3.5 Flash |
|----------|----------|----------|
| Creator | OpenAI | StepFun |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Non-Reasoning |
| Context | 200K | 256K |
| Independent public score (not head-to-head) | null | 42.03 |
| Benchmarks Covered | 7 | 3 |
| Pricing (input/output) | $1.10 / $4.40 | $0.10 / $0.30 |

## Category Breakdown

### Coding

- Winner: Insufficient shared evidence
- o4-mini public-lane score: Coming soon
- Step 3.5 Flash public-lane score: Coming soon

| Benchmark | o4-mini | Step 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| HumanEval | 97.3% | Coming soon | Coming soon |
| SWE-bench Verified | Coming soon | 74.4% | Coming soon |
| LiveCodeBench v6 | Coming soon | 86.4% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- o4-mini public-lane score: 66.9 (Unranked · 3 rankable rows)
- Step 3.5 Flash public-lane score: Coming soon

| Benchmark | o4-mini | Step 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| DROP | 77.7% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- o4-mini public-lane score: 67.4 (Unranked · 1 rankable row)
- Step 3.5 Flash public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- o4-mini public-lane score: Coming soon
- Step 3.5 Flash public-lane score: Coming soon

| Benchmark | o4-mini | Step 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| MMLU | 90% | Coming soon | Coming soon |
| GPQA | 77.6% | Coming soon | Coming soon |
| SimpleQA | 20.2% | Coming soon | Coming soon |

### Multilingual

- Winner: Insufficient shared evidence
- o4-mini public-lane score: Coming soon
- Step 3.5 Flash public-lane score: Coming soon

| Benchmark | o4-mini | Step 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| MGSM | 93.7% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- o4-mini public-lane score: 83.9 (#55/153)
- Step 3.5 Flash public-lane score: Coming soon

### Mathematics

- Winner: Insufficient shared evidence
- o4-mini public-lane score: Coming soon
- Step 3.5 Flash public-lane score: Coming soon

| Benchmark | o4-mini | Step 3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| MATH-500 | 97.5% | Coming soon | Coming soon |
| AIME 2025 | Coming soon | 97.3% | Coming soon |

## FAQ

### Can I compare o4-mini and Step 3.5 Flash on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [o4-mini vs o4-mini (high)](/compare/o4-mini-vs-o4-mini-high)
- [Step 3.5 Flash vs o4-mini (high)](/compare/o4-mini-high-vs-step-3-5-flash)
- [o4-mini vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-o4-mini)
- [Step 3.5 Flash vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-step-3-5-flash)

## Explore More

- [o4-mini profile](/models/o4-mini)
- [Step 3.5 Flash profile](/models/step-3-5-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)