# Claude 3.5 Haiku vs GPT-OSS 20B

> Side-by-side benchmark comparison for Claude 3.5 Haiku and GPT-OSS 20B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-3-5-haiku-vs-gpt-oss-20b
- Last updated: October 14, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Pick Claude 3.5 Haiku if you want the stronger benchmark profile. GPT-OSS 20B only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude 3.5 Haiku leads overall 47 to 33.13.
- The biggest single benchmark swing is AIME 2024 in Mathematics, with scores of 5.3% and 92.1%.
- Claude 3.5 Haiku also has the larger context window at 200K.

## Model Snapshot

| Property | Claude 3.5 Haiku | GPT-OSS 20B |
|----------|----------|----------|
| Creator | Anthropic | OpenAI |
| Type | Proprietary | Open Weight |
| Reasoning | Non-Reasoning | Non-Reasoning |
| Context | 200K | 128K |
| Overall Score | null | 33.13 |
| Benchmarks Covered | 10 | 7 |
| Pricing (input/output) | N/A | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: 14.6 (Estimated · #112/124)

### Coding

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: 18.6 (Estimated · #122/149)

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| HumanEval | 88.1% | Coming soon | Coming soon |
| SWE-bench Verified | 40.6% | 60.7% | GPT-OSS 20B |
| React Native Evals | Coming soon | 71% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: 49.7 (Unranked · 2 rankable rows)

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| BBH | 86.6% | Coming soon | Coming soon |
| DROP | 83.1% | Coming soon | Coming soon |

### Knowledge

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: 34.1 (Supported · #137/181)

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 41.6% | 71.5% | GPT-OSS 20B |
| MMLU-Pro | 65% | Coming soon | Coming soon |
| MMLU | 80.3% | 85.3% | GPT-OSS 20B |
| HLE | Coming soon | 10.9% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: Coming soon

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| MGSM | 85.6% | Coming soon | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: 79.2 (#57/128)

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 85.9% | Coming soon | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude 3.5 Haiku public-lane score: Coming soon
- GPT-OSS 20B public-lane score: Coming soon

| Benchmark | Claude 3.5 Haiku | GPT-OSS 20B | Winner |
|-----------|-----------|-----------|--------|
| AIME 2024 | 5.3% | 92.1% | GPT-OSS 20B |
| AIME 2025 | Coming soon | 91.7% | Coming soon |

## FAQ

### Which is better overall, Claude 3.5 Haiku or GPT-OSS 20B?

Claude 3.5 Haiku is ahead overall on BenchLM right now.

### How many benchmarks does Claude 3.5 Haiku cover on BenchLM?

Claude 3.5 Haiku currently has 10 sourced benchmark scores on BenchLM.

### How many benchmarks does GPT-OSS 20B cover on BenchLM?

GPT-OSS 20B currently has 7 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude 3.5 Haiku vs GPT-OSS 120B](/compare/claude-3-5-haiku-vs-gpt-oss-120b)
- [GPT-OSS 20B vs GPT-OSS 120B](/compare/gpt-oss-120b-vs-gpt-oss-20b)
- [Claude 3.5 Haiku vs Claude Opus 5.5](/compare/claude-3-5-haiku-vs-claude-opus-5-5)
- [GPT-OSS 20B vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-gpt-oss-20b)

## Explore More

- [Claude 3.5 Haiku profile](/models/claude-3-5-haiku)
- [GPT-OSS 20B profile](/models/gpt-oss-20b)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)