# Claude 4 Sonnet vs GPT-5.5 Pro

> Side-by-side benchmark comparison for Claude 4 Sonnet and GPT-5.5 Pro across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-4-sonnet-vs-gpt-5-5-pro
- Last updated: September 4, 2026

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

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for Claude 4 Sonnet and GPT-5.5 Pro.

## Summary

- Claude 4 Sonnet and GPT-5.5 Pro 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 | Claude 4 Sonnet | GPT-5.5 Pro |
|----------|----------|----------|
| Creator | Anthropic | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 200K | 1M |
| Independent public score (not head-to-head) | 41.76 | 63.07 |
| Benchmarks Covered | 3 | 6 |
| Pricing (input/output) | $3.00 / $15.00 | $30.00 / $180.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 42.3 (Estimated · #115/151)
- GPT-5.5 Pro public-lane score: 60.6 (Estimated · #24/151)

| Benchmark | Claude 4 Sonnet | GPT-5.5 Pro | Winner |
|-----------|-----------|-----------|--------|
| Gert Labs | 39.66% | Coming soon | Coming soon |
| JobBench | 18.4% | Coming soon | Coming soon |
| BrowseComp | Coming soon | 90.1% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 38 (Supported · #149/183)
- GPT-5.5 Pro public-lane score: Coming soon

| Benchmark | Claude 4 Sonnet | GPT-5.5 Pro | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 72.7% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 51.9 (Unranked · 1 rankable row)
- GPT-5.5 Pro public-lane score: Coming soon

### Reasoning

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 53.9 (Unranked · 2 rankable rows)
- GPT-5.5 Pro public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 41 (Estimated · #134/181)
- GPT-5.5 Pro public-lane score: 61.1 (Estimated · #36/181)

| Benchmark | Claude 4 Sonnet | GPT-5.5 Pro | Winner |
|-----------|-----------|-----------|--------|
| HLE | Coming soon | 57.2% | Coming soon |
| HLE w/o tools | Coming soon | 43.1% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: 53.4 (#75/120)
- GPT-5.5 Pro public-lane score: Coming soon

### Mathematics

- Winner: Insufficient shared evidence
- Claude 4 Sonnet public-lane score: Coming soon
- GPT-5.5 Pro public-lane score: 70.2 (Unranked · 3 rankable rows)

| Benchmark | Claude 4 Sonnet | GPT-5.5 Pro | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | Coming soon | 52.4% | Coming soon |
| FrontierMath v2 (Tiers 1-3) | Coming soon | 51.000% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 39.600% | Coming soon |

## FAQ

### Can I compare Claude 4 Sonnet and GPT-5.5 Pro 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

- [Claude 4 Sonnet vs GPT-5.5](/compare/claude-4-sonnet-vs-gpt-5-5)
- [GPT-5.5 Pro vs GPT-5.5](/compare/gpt-5-5-vs-gpt-5-5-pro)
- [Claude 4 Sonnet vs Claude Fable 5.1](/compare/claude-4-sonnet-vs-claude-fable-5-1)
- [GPT-5.5 Pro vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gpt-5-5-pro)

## Explore More

- [Claude 4 Sonnet profile](/models/claude-4-sonnet)
- [GPT-5.5 Pro profile](/models/gpt-5-5-pro)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)