# GPT-5.5 Pro vs Kimi K2.5 (Reasoning)

> Side-by-side benchmark comparison for GPT-5.5 Pro and Kimi K2.5 (Reasoning) across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-5-pro-vs-kimi-k2-5-reasoning
- Last updated: September 4, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-5.5 Pro and Kimi K2.5 (Reasoning) share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Kimi K2.5 (Reasoning) has the lower published output-token price.
- GPT-5.5 Pro has the larger published context window at 1M.

## Model Snapshot

| Property | GPT-5.5 Pro | Kimi K2.5 (Reasoning) |
|----------|----------|----------|
| Creator | OpenAI | Moonshot AI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 128K |
| Independent public score (not head-to-head) | 63.07 | 58.74 |
| Benchmarks Covered | 6 | 9 |
| Pricing (input/output) | $30.00 / $180.00 | $0.60 / $3.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 60.6 (Estimated · #24/151)
- Kimi K2.5 (Reasoning) public-lane score: 49.9 (Estimated · #67/151)

| Benchmark | GPT-5.5 Pro | Kimi K2.5 (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| BrowseComp | 90.1% | 60.6% | GPT-5.5 Pro |
| Terminal-Bench 2.0 | Coming soon | 50.8% | Coming soon |
| Gert Labs | Coming soon | 32.58% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: Coming soon
- Kimi K2.5 (Reasoning) public-lane score: 52.9 (Estimated · #52/183)

| Benchmark | GPT-5.5 Pro | Kimi K2.5 (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | Coming soon | 76.8% | Coming soon |
| Vibe Code Bench | Coming soon | 17.54% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: Coming soon
- Kimi K2.5 (Reasoning) public-lane score: 63.2 (Unranked · 1 rankable row)

| Benchmark | GPT-5.5 Pro | Kimi K2.5 (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | Coming soon | 78.5% | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 61.1 (Estimated · #36/181)
- Kimi K2.5 (Reasoning) public-lane score: 52.4 (Estimated · #78/181)

| Benchmark | GPT-5.5 Pro | Kimi K2.5 (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| HLE | 57.2% | Coming soon | Coming soon |
| HLE w/o tools | 43.1% | Coming soon | Coming soon |
| GPQA | Coming soon | 87.6% | Coming soon |
| MMLU-Pro | Coming soon | 87.1% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-5.5 Pro public-lane score: 70.2 (Unranked · 3 rankable rows)
- Kimi K2.5 (Reasoning) public-lane score: Coming soon

| Benchmark | GPT-5.5 Pro | Kimi K2.5 (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 52.4% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 51.000% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 39.600% | Coming soon | Coming soon |
| AIME 2025 | Coming soon | 96.1% | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-5.5 Pro and Kimi K2.5 (Reasoning)?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GPT-5.5 Pro vs GPT-5.5](/compare/gpt-5-5-vs-gpt-5-5-pro)
- [Kimi K2.5 (Reasoning) vs GPT-5.5](/compare/gpt-5-5-vs-kimi-k2-5-reasoning)
- [GPT-5.5 Pro vs Kimi K2.5](/compare/gpt-5-5-pro-vs-kimi-k2-5)
- [Kimi K2.5 (Reasoning) vs Kimi K2.5](/compare/kimi-k2-5-vs-kimi-k2-5-reasoning)

## Explore More

- [GPT-5.5 Pro profile](/models/gpt-5-5-pro)
- [Kimi K2.5 (Reasoning) profile](/models/kimi-k2-5-reasoning)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)