Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token...
Model details →Anthropic: Claude Opus 4.8 vs OpenAI: GPT-5.5
Anthropic: Claude Opus 4.8 and OpenAI: GPT-5.5 are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token...
Model details →Side-by-side comparison
| Capability | Anthropic: Claude Opus 4.8 | OpenAI: GPT-5.5 | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 1M | 1.1M | 🏆 OpenAI: GPT-5.5 |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $5.00 | $5.00 | Tie |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $25.00 | $30.00 | 🏆 Anthropic: Claude Opus 4.8 |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is Anthropic: Claude Opus 4.8 better than OpenAI: GPT-5.5?
Anthropic: Claude Opus 4.8 and OpenAI: GPT-5.5 are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
What's the price difference between Anthropic: Claude Opus 4.8 and OpenAI: GPT-5.5?
Input: $5.00 vs $5.00 per 1M tokens. Output: $25.00 vs $30.00 per 1M tokens.
What context windows do Anthropic: Claude Opus 4.8 and OpenAI: GPT-5.5 support?
Anthropic: Claude Opus 4.8 supports up to 1M tokens. OpenAI: GPT-5.5 supports up to 1.1M tokens.
Do both Anthropic: Claude Opus 4.8 and OpenAI: GPT-5.5 support tool calling?
Anthropic: Claude Opus 4.8: yes. OpenAI: GPT-5.5: yes.
Compare Anthropic: Claude Opus 4.8 with other models
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