# GPT-6 Astra vs Mercury 2.5

> Side-by-side benchmark comparison for GPT-6 Astra and Mercury 2.5 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gpt-6-astra-vs-mercury-2-5
- Last updated: September 8, 2026

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

## Quick Verdict

Evidence is too thin for a benchmark verdict: GPT-6 Astra and Mercury 2.5 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.
- Mercury 2.5 has the lower published output-token price.
- GPT-6 Astra has the larger published context window at 1.05M.

## Model Snapshot

| Property | GPT-6 Astra | Mercury 2.5 |
|----------|----------|----------|
| Creator | OpenAI | Inception |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1.05M | 260K |
| Independent public score (not head-to-head) | 84.11 | null |
| Benchmarks Covered | 25 | 5 |
| Pricing (input/output) | $10.00 / $50.00 | $0.04 / $0.15 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 70.4 (Supported · #5/152)
- Mercury 2.5 public-lane score: 44.5 (Estimated · #91/152)

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| BrowseComp | 91.5% | Coming soon | Coming soon |
| OSWorld 2.0 | 72.6% | Coming soon | Coming soon |
| Terminal-Bench 4.0 | 57.90% | Coming soon | Coming soon |
| Terminal-Bench-Science 0.1 | 64.6% | Coming soon | Coming soon |
| ExploitGym | 42.4% | Coming soon | Coming soon |
| Agents' Last Exam | 59.3% | Coming soon | Coming soon |
| AutomationBench | 41.4% | Coming soon | Coming soon |
| HLE w/ tools | 57.2% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 87.3% | Coming soon | Coming soon |
| τ³-bench results | Coming soon | 96.0% | Coming soon |
| DeepSearchQA | Coming soon | 34.0% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 74.6 (Supported · #4/151)
- Mercury 2.5 public-lane score: 47.8 (Estimated · #73/151)

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| deepSwe | 74.1% | Coming soon | Coming soon |
| FrontierCode 1.1 Main | 53.3% | Coming soon | Coming soon |
| FrontierCode 1.1 Extended | 64.5% | Coming soon | Coming soon |
| SciCode | Coming soon | 38% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 82.8 (Unranked · 3 rankable rows)
- Mercury 2.5 public-lane score: Coming soon

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| ScreenSpot Pro | 92.7% | Coming soon | Coming soon |
| BenchCAD Vision2Code (tools) | 0.959 | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 89.5 (#1/18)
- Mercury 2.5 public-lane score: 67.7 (Unranked · 1 rankable row)

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-1 | 98.50% | Coming soon | Coming soon |
| ARC-AGI-2 | 95% | Coming soon | Coming soon |
| ARC-AGI-3 | 62.7% | Coming soon | Coming soon |
| GeneBench-Pro | 37.8% | Coming soon | Coming soon |
| MRCR v2 256K-512K | 100.0% | Coming soon | Coming soon |
| MRCR v2 512K-1M | 96.3% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 82.3 (Supported · #3/182)
- Mercury 2.5 public-lane score: 48.3 (Estimated · #94/182)

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 96% | Coming soon | Coming soon |
| GPQA-D | 96.0% | 79.0% | GPT-6 Astra |
| HealthBench Professional | 63.4% | Coming soon | Coming soon |
| HealthBench Hard | 36.3% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: Coming soon
- Mercury 2.5 public-lane score: 80.1 (#53/121)

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| IFBench | Coming soon | 77% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- GPT-6 Astra public-lane score: 85.2 (Unranked · 1 rankable row)
- Mercury 2.5 public-lane score: Coming soon

| Benchmark | GPT-6 Astra | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tier 4) | 97.600% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GPT-6 Astra and Mercury 2.5?

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-6 Astra vs Mercury 2.5 Preview](/compare/gpt-6-astra-vs-mercury-2-5-preview)
- [Mercury 2.5 vs Mercury 2.5 Preview](/compare/mercury-2-5-vs-mercury-2-5-preview)
- [GPT-6 Astra vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gpt-6-astra)
- [Mercury 2.5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-mercury-2-5)

## Explore More

- [GPT-6 Astra profile](/models/gpt-6-astra)
- [Mercury 2.5 profile](/models/mercury-2-5)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)