GPT-5.5 (xhigh)
ModelActiveby OpenAI · family “gpt-xhigh”
Epoch Capabilities Index
Not scored by Epoch AI
Released
23 Apr 2026
Context window
Unknown
Max output
Unknown
Input $ / 1M tokens
Unknown
Output $ / 1M tokens
Unknown
Cached input $ / 1M
Unknown
Each benchmark shown separately with its own source
Benchmark results (22)
| Benchmark | Domain | Score | vs best recorded | Setting | Run | Source |
|---|---|---|---|---|---|---|
| Furniture Assembly | multimodal | 44.2% ±6.4 | 53% | xhigh | 10 Sep 2026 | Epoch ↗ |
| LMCA | agents | 54.3% | 80% | xhigh | — | External ↗ |
| DTBench | reasoning | 96.0% | 97% | xhigh | — | External ↗ |
| Mystery Game Puzzles | games | 56.0% ±5.0 | 67% | xhigh | 24 Jul 2026 | Epoch ↗ |
| EBR-bench | reasoning | 34.3% ±2.0 | 45% | xhigh | 27 Jul 2026 | Epoch ↗ |
| OSWorld 2.0 | agents | 13.0% | 41% | xhigh | — | External ↗ |
| FrontierMath-Tiers-1-3-v2-Private | math | 85.3% ±2.1 | 91% | xhigh | 11 Jun 2026 | Epoch ↗ |
| FrontierMath-Tier-4-v2-Private | math | 72.5% ±7.1 | 74% | xhigh | 11 Jun 2026 | Epoch ↗ |
| DeepSWE | coding | 67.0% | 90% | xhigh | — | External ↗ |
| PostTrainBench | agents | 27.2% | 65% | xhigh | — | External ↗ |
| ProofBench | math | 50.0% | 50% | xhigh | — | External ↗ |
| Chess Puzzles | games | 54.0% ±5.0 | 75% | xhigh | 24 Apr 2026 | Eval log ↗ |
| SimpleQA Verified | knowledge | 63.0% ±1.5 | 83% | xhigh | 27 Aug 2026 | Eval log ↗ |
| FrontierMath-Tier-4-2025-07-01-Privatesuperseded | math | 35.4% ±6.9 | 74% | xhigh | 23 Apr 2026 | Epoch ↗ |
| GSO-Bench | coding | 40.2% | 85% | xhigh | — | External ↗ |
| ARC-AGI-2 | reasoning | 85.0% | 89% | xhigh | — | External ↗ |
| FrontierMath-2025-02-28-Privatesuperseded | math | 51.7% ±2.9 | 99% | xhigh | 23 Apr 2026 | Epoch ↗ |
| WeirdML | coding | 84.9% ±0.0 | 91% | xhigh | — | External ↗ |
| OTIS Mock AIME 2024-2025 | math | 100.0% | 100% | xhigh | 24 Apr 2026 | Eval log ↗ |
| SWE-Bench verified | coding | 80.6% ±1.8 | 97% | xhigh | 24 Apr 2026 | Eval log ↗ |
| GPQA diamond | science | 94.0% ±1.5 | 98% | xhigh | 24 Apr 2026 | Eval log ↗ |
| ARC-AGI | reasoning | 95.0% | 96% | xhigh | — | External ↗ |
Source: Epoch AI Benchmarking Hub (CC BY 4.0). “External” rows are leaderboard results Epoch collects from third parties. Best reported setting per benchmark is shown.
API list price over time
Price history
$ per 1M tokens
This model has no public API price listing
0 recorded prices on — (OpenRouter listing); re-read on every data refresh, most recently 7h ago. Steps show when the price changed.
Events
- BenchmarkEpoch AI evaluates GPT-5.5 (xhigh)Epoch AI Benchmarking Hub
- BenchmarkEpoch AI evaluates GPT-5.5 (xhigh)Epoch AI Benchmarking Hub
- Model launchMajorOpenAI releases GPT-5.5 (xhigh)Epoch AI Benchmarking Hub