Claude Opus 4.5 vs Claude Opus 4.6
Different efforts: non-thinking · high · Compare all at high
Humanity's Last Exam Humanity's Last Exam: Very hard expert questions across many fields, written to stump today’s models
Opus 4.513.2
Opus 4.619.1
Arena Text · creative writing Arena Text · creative writing: Human pairwise preferences in the stated text vote pool
Opus 4.5 · high1,469
Opus 4.61,500
MMMU-Pro (vision) MMMU-Pro (vision): College-level questions that require understanding images: charts, diagrams, photos
Opus 4.571.2
Opus 4.672.5
| Benchmark | Opus 4.5 | Opus 4.6 |
|---|---|---|
| Humanity's Last Exam | 13.2 | 19.1 |
| Arena Text · creative writing | 1,469 · high | 1,500 |
| MMMU-Pro (vision) | 71.2 | 72.5 |
Specs
| Spec | Opus 4.5 | Opus 4.6 |
|---|---|---|
| Input, per 1M | $5 | $5 |
| Output, per 1M | $25 | $25 |
| Speed, tok/s | 51 | 45 |
| Context | 200K | 1M |
| Weights | Closed | Closed |
| Released | Nov 2025 | Feb 2026 |
| See images | ✓ | ✓ |
| Read PDFs | Partial | Partial |
| Hear audio | — | — |
| Watch video | — | — |
| Call tools | ✓ | ✓ |
| Force a tool call | Partial | Partial |
| Return strict JSON | ✓ | ✓ |
| Search the web | ? | ? |
| Run code | ? | ? |
| Use a computer | ? | ? |
What breaks when you switch
Opus 4.5 → Opus 4.6
Nothing known.
Opus 4.6 → Opus 4.5