# GPT-5 Pro vs Mercury 2.5

> GPT-5 Pro is the stronger model overall, scoring 46.4 to 33.5 on the Noometry Index. Mercury 2.5 costs 611× less per token, which makes it the better buy when GPT-5 Pro's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gpt-5-pro-vs-mercury-2-5
- Last updated: 2026-10-12
- Shared benchmarks: 0

## Summary

- The widest gap is in math, where GPT-5 Pro leads 48.5 to 23.3.
- Mercury 2.5 is cheaper at $0.04 / $0.15 per million input/output tokens, against $15 / $120 for GPT-5 Pro.
- GPT-5 Pro accepts more context: 400K tokens versus 260K.

## Snapshot

| | GPT-5 Pro | Mercury 2.5 |
|---|---|---|
| Provider | OpenAI | Inception |
| Noometry Index | 46.4 | 33.5 |
| Rank | 64 | 242 |
| Context | 400K | 260K |
| Input $/M | $15 | $0.04 |
| Output $/M | $120 | $0.15 |
| Weights | Proprietary | Proprietary |

## Coding

- GPT-5 Pro: 44.0 (#80)
- Mercury 2.5: 39.5 (#156)

| Benchmark | GPT-5 Pro | Mercury 2.5 |
|---|---|---|
| SciCode | — | 38.5% |
| WeirdML | 60.4% | — |
| ALE-Bench | — | 301.65 |
| AlgoTune | 1.31 | — |

## Reasoning

- GPT-5 Pro: 38.9 (#62)
- Mercury 2.5: 22.4 (#193)

| Benchmark | GPT-5 Pro | Mercury 2.5 |
|---|---|---|
| ARC-AGI-2 | 18.3% | — |
| SimpleBench | 61.6% | — |
| Kagi LLM Benchmark | 76.8% | — |
| ARC-AGI-1 | 70.2% | — |
| CritPt | — | 0% |
| EnigmaEval | 18.8% | — |
| Epoch Capabilities Index | 150.28 | — |

## Math

- GPT-5 Pro: 48.5 (#63)
- Mercury 2.5: 23.3 (#272)

| Benchmark | GPT-5 Pro | Mercury 2.5 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 55.8% | — |
| FrontierMath Tier 4 | 19.5% | — |
| ProofBench | — | 3% |
| FrontierMath Tier 4 (v1) | 14.6% | — |

## Knowledge

- GPT-5 Pro: 56.7 (#42)
- Mercury 2.5: —

| Benchmark | GPT-5 Pro | Mercury 2.5 |
|---|---|---|
| Humanity's Last Exam | 31.6% | — |

## FAQ

### Is GPT-5 Pro better than Mercury 2.5?

GPT-5 Pro is the stronger model overall, scoring 46.4 to 33.5 on the Noometry Index. Mercury 2.5 costs 611× less per token, which makes it the better buy when GPT-5 Pro's lead doesn't matter for your workload.

### Which is cheaper, GPT-5 Pro or Mercury 2.5?

Mercury 2.5 is cheaper. It lists at $0.04 per million input tokens and $0.15 per million output tokens; GPT-5 Pro lists at $15 and $120.

### Is GPT-5 Pro or Mercury 2.5 better for coding?

GPT-5 Pro scores higher on coding benchmarks: 44.0 versus 39.5 in the Noometry coding category.

### Which has the bigger context window?

GPT-5 Pro does, with 400K tokens against 260K.

### How many benchmarks do GPT-5 Pro and Mercury 2.5 share?

0 benchmarks have published results for both models. GPT-5 Pro has 12 scored results on Noometry and Mercury 2.5 has 4.