# GPT-5.5 vs GPT-6.1 Terra

> Side-by-side benchmark comparison for GPT-5.5 and GPT-6.1 Terra across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-5-5-vs-gpt-6-1-terra
- Last updated: October 26, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-5.5 and GPT-6.1 Terra 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.
- GPT-6.1 Terra has the lower published output-token price.
- GPT-6.1 Terra has the larger published context window at 1.05M.

## Model Snapshot

| Property | GPT-5.5 | GPT-6.1 Terra |
|----------|----------|----------|
| Creator | OpenAI | OpenAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1.05M |
| Independent public score (not head-to-head) | 69.03 | 75.87 |
| Benchmarks Covered | 44 | 10 |
| Pricing (input/output) | $5.00 / $30.00 | $1.00 / $5.00 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 60.5 (Supported · #27/133)
- GPT-6.1 Terra public-lane score: 72.4 (Estimated · #8/133)

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 82% | Coming soon | Coming soon |
| CyberGym | 81.8% | Coming soon | Coming soon |
| BrowseComp | 84.4% | Coming soon | Coming soon |
| OSWorld-Verified | 78.7% | Coming soon | Coming soon |
| MCP Atlas | 75.3% | Coming soon | Coming soon |
| Toolathlon | 55.6% | Coming soon | Coming soon |
| τ²-bench results | 98% | Coming soon | Coming soon |
| Gert Labs | 72.93% | Coming soon | Coming soon |
| ResearchClawBench | 17.0% | Coming soon | Coming soon |
| OSWorld 2.0 | 13.0% | Coming soon | Coming soon |
| JobBench | 42.7% | Coming soon | Coming soon |
| ExploitGym | 13.4% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 76.4% | Coming soon | Coming soon |
| ApprenticeBench | 20% | Coming soon | Coming soon |
| MazeBench | 0% | Coming soon | Coming soon |
| Terminal-Bench 4.0 | Coming soon | 50.30% | Coming soon |
| Terminal-Bench-Science 0.1 | Coming soon | 58.3% | Coming soon |
| Agents' Last Exam | Coming soon | 60.0% | Coming soon |
| OSWorld 2.1 Offline | Coming soon | 74.2% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 62.1 (Supported · #15/154)
- GPT-6.1 Terra public-lane score: Coming soon

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 58.6% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 82.0% | Coming soon | Coming soon |
| Vibe Code Bench | 69.85% | Coming soon | Coming soon |
| React Native Evals | 84.7% | Coming soon | Coming soon |
| cursorBench31 | 59.2% | Coming soon | Coming soon |
| CursorBench 3.2 | 58.4% | Coming soon | Coming soon |
| FrontierCode 1.1 Main | 43.0% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 85.3% | Coming soon | Coming soon |
| SWE-bench (Vals) | 82.6% | Coming soon | Coming soon |
| PostTrainBench v1.1 | 27.2% | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 69.7 (#17/26)
- GPT-6.1 Terra public-lane score: 81.8 (Unranked · 2 rankable rows)

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| MRCR v2 64K-128K | 83.1% | Coming soon | Coming soon |
| MRCR v2 128K-256K | 87.5% | Coming soon | Coming soon |
| ARC-AGI-2 | 85% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.4% | Coming soon | Coming soon |
| ARC-AGI-1 | 95.00% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 74.4 (#28/58)
- GPT-6.1 Terra public-lane score: 91.6 (#4/58)

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| ExtractBench (LlamaIndex) | 93.57% | Coming soon | Coming soon |
| ParseBench | 66.63% | Coming soon | Coming soon |
| MMMU-Pro | 81.2% | 85.5% | GPT-6.1 Terra |
| MMMU-Pro w/ Python | 83.2% | Coming soon | Coming soon |
| OfficeQA Pro | 54.1% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 71.2 (Supported · #16/188)
- GPT-6.1 Terra public-lane score: 74.9 (Supported · #12/188)

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 93.6% | Coming soon | Coming soon |
| GPQA-D | 93.6% | Coming soon | Coming soon |
| HLE | 52.2% | Coming soon | Coming soon |
| HLE w/o tools | 41.4% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 93.2% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 88.1% | Coming soon | Coming soon |
| HealthBench (raw) | Coming soon | 51.1% | Coming soon |
| HealthBench (length-adjusted) | Coming soon | 55.1% | Coming soon |
| HealthBench Professional | Coming soon | 62.7% | Coming soon |
| HealthBench Professional (raw) | Coming soon | 64.2% | Coming soon |
| HealthBench Hard | Coming soon | 31.4% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 93.3 (#9/155)
- GPT-6.1 Terra public-lane score: Coming soon

### Mathematics

- Winner: Insufficient shared evidence
- GPT-5.5 public-lane score: 91.2 (Unranked · 3 rankable rows)
- GPT-6.1 Terra public-lane score: Coming soon

| Benchmark | GPT-5.5 | GPT-6.1 Terra | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 51.7% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 85.263% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 72.500% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-5.5 and GPT-6.1 Terra?

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 vs GPT-5.5 Pro](/compare/gpt-5-5-vs-gpt-5-5-pro)
- [GPT-6.1 Terra vs GPT-5.5 Pro](/compare/gpt-5-5-pro-vs-gpt-6-1-terra)
- [GPT-5.5 vs GPT-6 Astra](/compare/gpt-5-5-vs-gpt-6-astra)
- [GPT-6.1 Terra vs GPT-6 Astra](/compare/gpt-6-1-terra-vs-gpt-6-astra)

## Explore More

- [GPT-5.5 profile](/models/gpt-5-5)
- [GPT-6.1 Terra profile](/models/gpt-6-1-terra)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)
