Claude 4.8 Opus vs GPT-5.5
Direct spec comparison of Claude 4.8 Opus (from Anthropic) and GPT-5.5 (from OpenAI). Want a 3- or 4-way comparison? Open the multi-model tool →
 Claude 4.8 OpusAnthropic |  GPT-5.5OpenAI | |
|---|---|---|
| Vendor | Anthropic | OpenAI |
| Family | Claude | GPT |
| Release date | 2026-05-28 | 2026-04-23 |
| Context window | 1,000,000 tokens | 400,000 tokens |
| Parameters | — | — |
| Modality | text, vision | text, vision, audio |
| License | proprietary | proprietary |
| Source | proprietary | proprietary |
| Description | Anthropic's flagship hybrid-reasoning model — Opus 4.8 pushes coding and AI-agent workflows further (agentic coding 69.2% vs 64.3% on 4.7; multidisciplinary reasoning 57.9% vs 54.7%). 1M-token context, $5/$25 per MTok pricing held flat from Opus 4.7. Introduces Dynamic Workflows for Claude Code (research preview). GA on Anthropic API (`claude-opus-4-8`), AWS Bedrock, Google Vertex, Microsoft Foundry, and GitHub Copilot. | OpenAI's smartest and most intuitive model — successor to GPT-5, with major coding, research, and document workflow gains. GPT-5.5 Pro variant also available for heavier reasoning. |
| Links | ||
| Benchmarks | ||
| MMLU-Pro | — | 87.6% |
| GPQA-D | — | 89.4% |
| HumanEval | — | 96.8% |
| Aider | — | 89.7% |
| AIME-25 | — | 94.2% |
| LiveCB | — | 78.9% |
| MMMU | — | 78.4% |
More like this
Looking for a different head-to-head? Build your own comparison on the multi-model tool.
Or see all Claude 4.8 Opus details / GPT-5.5 details.