Compare / Claude Opus 4.6 vs GPT-5.6 Terra
Claude Opus 4.6 vs GPT-5.6 Terra
21 results from 6 sources that measured both models. Each row is in the source's own units; there is no overall winner.
| Benchmark | Metric | Claude Opus 4.6 | GPT-5.6 Terra |
|---|---|---|---|
| APEX-Agentsreported | Tasks passed% of tasks | 46.3% | 58.2% |
| Arena (formerly LMArena)reported | OverallArena rating | 1,495 | 1,477 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,494 | 1,467 |
| Arena (formerly LMArena)reported | Business, management and financeArena rating | 1,501 | 1,466 |
| Arena (formerly LMArena)reported | Creative writingArena rating | 1,501 | 1,428 |
| Arena (formerly LMArena)reported | Expert promptsArena rating | 1,547 | 1,504 |
| Arena (formerly LMArena)reported | Instruction followingArena rating | 1,513 | 1,462 |
| Arena (formerly LMArena)reported | OverallArena rating | 1,505 | 1,465 |
| Arena (formerly LMArena)reported | Writing, literature and languageArena rating | 1,500 | 1,445 |
| Artificial Analysisreported | Artificial Analysis Intelligence Indexindex score | 31.9 | 42.1 |
| Artificial Analysisreported | GPQA Diamond% of questions | 89.6% | 92.5% |
| Artificial Analysisreported | Humanity's Last Exam% of questions | 39.9% | 42.9% |
| Artificial Analysisreported | IFBench% of instructions | 53.1% | 71.2% |
| Artificial Analysisreported | Long-context reasoning (AA-LCR)% of questions | 78.0% | 83.0% |
| Artificial Analysisreported | Terminal-Bench Hard% of tasks | 48.5% | 62.9% |
| Artificial Analysisreported | Τ²-bench telecom% of tasks | 92.1% | 86.3% |
| SimpleQA Verified (Epoch AI)reported | Correct answers% of questions | 47.0% | 43.2% |
| UGI Leaderboardreported | Requested-length error% off the requested word count | 3.0% | 22.0% |
| UGI Leaderboardreported | Style adherencescore from 0 to 1 | 0.41 | 0.39 |
| UGI Leaderboardreported | Writing scorescore out of 100 | 70.9 | 60.4 |
| Vending-Bench 2reported | Money after a yearUS dollars | $8,017.59 | $7,343.21 |
Bold green marks the better value on that metric. Where a source reports ranges that overlap, the difference may not be meaningful; see the benchmark page for ranges.