# Claude Opus 4.5 vs o4-mini

> Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 41.6 on the Noometry Index. o4-mini costs 5.2× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-opus-4-5-vs-o4-mini
- Last updated: 2026-10-10
- Shared benchmarks: 47

## Summary

- They share 47 benchmarks with published results for both. Claude Opus 4.5 scores higher in 8 categories and o4-mini in 2 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Claude Opus 4.5 leads 42.5 to 24.6.
- The biggest single-benchmark swing is SWE-bench Verified (bash only): 76.8% for Claude Opus 4.5 and 45% for o4-mini.
- o4-mini is cheaper at $1.10 / $4.40 per million input/output tokens, against $5 / $25 for Claude Opus 4.5.

## Snapshot

| | Claude Opus 4.5 | o4-mini |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Noometry Index | 50.5 | 41.6 |
| Rank | 39 | 119 |
| Context | 200K | 200K |
| Input $/M | $5 | $1.10 |
| Output $/M | $25 | $4.40 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 4.5: 55.4 (#21)
- o4-mini: 41.6 (#110)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| SWE-bench Verified (bash only) | 76.8% | 45% |
| GSO | 26.5% | 3.6% |
| WeirdML | 63.7% | 52.6% |
| LMArena Coding | 1504 | 1369 |
| ALE-Bench | 1,025 | 826.17 |
| AlgoTune | 1.77 | 1.72 |
| SWE-bench Verified | 76.7% | — |
| Aider Polyglot | — | 72% |
| LMArena WebDev | 1493 | — |
| SWE-bench Multilingual | 70.7% | — |
| CadEval | — | 62% |

## Agentic & Tool Use

- Claude Opus 4.5: 47.2 (#11)
- o4-mini: 32.3 (#57)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| Berkeley Function Calling Leaderboard | 77.5% | 53.2% |
| GDPval | 45.5% | 25.3% |
| METR Time Horizons | 75% | 63.9% |
| Terminal-Bench | 63.1% | — |
| Remote Labor Index | 3.8% | — |
| τ²-bench Airline | 84% | — |
| τ²-bench Banking | 24.7% | — |
| τ²-bench Retail | 79.6% | — |
| τ²-bench Telecom | 92.3% | — |
| Cybench | 82% | — |
| DeepResearch Bench | 54.8% | — |
| OSWorld | 66.3% | — |
| BALROG | 43.5% | — |
| LMArena Search | 1180 | — |
| Vending-Bench 2 | 4,967 | — |

## Reasoning

- Claude Opus 4.5: 42.5 (#43)
- o4-mini: 24.6 (#143)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| ARC-AGI-2 | 37.6% | 6.1% |
| SimpleBench | 62% | 38.7% |
| Kagi LLM Benchmark | 80.2% | 67.6% |
| ARC-AGI-1 | 80% | 58.7% |
| Chess Puzzles | 12% | 26% |
| EnigmaEval | 11.9% | 9.2% |
| LMArena Hard Prompts | 1476 | 1351 |
| Mystery Game Puzzles | 22% | 5% |
| DTBench | 89.9% | 77.6% |
| LMCA | 44.5% | 26.5% |
| Epoch Capabilities Index | 150.1 | 145.63 |
| ForecastBench | 60.7 | 61.8 |
| NYT Connections (extended) | 52.5% | — |
| CritPt | — | 0.6% |
| EBR-Bench | 14.3% | — |

## Math

- Claude Opus 4.5: 38.5 (#85)
- o4-mini: 40.2 (#79)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| FrontierMath (Tiers 1-3) | 34.4% | 36.1% |
| FrontierMath Tier 4 | 4.9% | 4.9% |
| OTIS Mock AIME 2024-2025 | 86.1% | 81.7% |
| LMArena Math | 1463 | 1390 |
| FrontierMath (Feb 2025 set) | 20.7% | 24.8% |
| FrontierMath Tier 4 (v1) | 4.2% | 6.3% |
| ProofBench | 36% | — |
| Omni-MATH | — | 72% |
| MATH Level 5 | — | 97.8% |

## Knowledge

- Claude Opus 4.5: 56.4 (#38)
- o4-mini: 43.5 (#83)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| GPQA Diamond | 86% | 79.6% |
| Humanity's Last Exam | 25.2% | 18.1% |
| SimpleQA Verified | 45.7% | 19.6% |
| Vectara Hallucination Rate | 10.9% | 18.6% |
| LMArena Expert | 1488 | 1344 |
| MMLU-Pro | — | 82% |
| Confabulations | — | 15.8% |
| GPQA (HELM) | — | 73.5% |

## Multimodal

- Claude Opus 4.5: 31.1 (#99)
- o4-mini: 39.5 (#46)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| GeoBench | 75% | 64% |
| VPCT | 40% | 57.5% |
| LMArena Vision | — | 1194 |
| Furniture Assembly | 28.3% | — |
| LMArena Document | 1462 | — |

## Multilingual

- Claude Opus 4.5: 54.5 (#45)
- o4-mini: 47.2 (#149)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| LMArena Non-English | 1438 | 1336 |
| LMArena Chinese | 1470 | 1355 |
| LMArena French | 1471 | 1362 |
| LMArena German | 1449 | 1336 |
| LMArena Japanese | 1415 | 1308 |
| LMArena Korean | 1424 | 1313 |
| LMArena Russian | 1448 | 1334 |
| LMArena Spanish | 1455 | 1346 |

## Instruction Following

- Claude Opus 4.5: 77.7 (#20)
- o4-mini: 75.4 (#63)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| LMArena Instruction Following | 1478 | 1321 |
| IFEval | — | 92.8% |

## Long Context

- Claude Opus 4.5: 46.4 (#21)
- o4-mini: 45.5 (#31)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| LMArena Longer Query | 1480 | 1315 |
| Fiction.LiveBench | — | 77.8% |
| CL-bench | 21.1% | — |

## Writing & Preference

- Claude Opus 4.5: 68.2 (#28)
- o4-mini: 54.2 (#148)

| Benchmark | Claude Opus 4.5 | o4-mini |
|---|---|---|
| LMArena Text | 1451 | 1353 |
| LMArena Creative Writing | 1445 | 1294 |
| LMArena Multi-Turn | 1466 | 1350 |
| Short-Story Creative Writing | — | 75% |
| EQ-Bench Creative Writing | 1687 | — |
| WildBench | — | 85.4% |

## FAQ

### Is Claude Opus 4.5 better than o4-mini?

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 41.6 on the Noometry Index. o4-mini costs 5.2× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Opus 4.5 or o4-mini?

o4-mini is cheaper. It lists at $1.10 per million input tokens and $4.40 per million output tokens; Claude Opus 4.5 lists at $5 and $25.

### Is Claude Opus 4.5 or o4-mini better for coding?

Claude Opus 4.5 scores higher on coding benchmarks: 55.4 versus 41.6 in the Noometry coding category.

### Which has the bigger context window?

Both accept 200K tokens.

### How many benchmarks do Claude Opus 4.5 and o4-mini share?

47 benchmarks have published results for both models. Claude Opus 4.5 has 69 scored results on Noometry and o4-mini has 60.