Claude Opus 4.8 vs GPT-5.5 Pro
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Quick verdict: which should you choose?
Choose Claude Opus 4.8 if you need
- ✓Choose GPT-5.5 Pro if you need a 1.05M-token context window for very long inputs.
- ✓Choose GPT-5.5 Pro if you need native seamless support for files, images, and text together.
- ✓Choose GPT-5.5 Pro if you need strong reasoning over the largest possible extended multimodal inputs.
Choose GPT-5.5 Pro if you need
- ✓Choose Claude Opus 4.8 if you need dramatically lower output pricing at $25 per million tokens.
- ✓Choose Claude Opus 4.8 if you need documented high output speed of 60.93 tokens per second.
- ✓Choose Claude Opus 4.8 if you need careful nuanced reasoning with robust safety alignment on long contexts.
- ✓Choose Claude Opus 4.8 if you need effective handling of 1M-token inputs at lower resource cost.
Verdict
GPT-5.5 Pro leads with a modestly larger context window and seamless multimodal integration for extended inputs, while Claude Opus 4.8 leads decisively on price and documented output speed. GPT-5.5 Pro suits maximum-context workloads despite higher cost and unknown speed metrics; Claude Opus 4.8 offers efficient, safety-tuned reasoning at far lower cost for million-token tasks. Neither supports audio or video, keeping the edge to text-image-file handling.
Claude Opus 4.8 vs GPT-5.5 Pro: side by side
| Spec | Claude Opus 4.8 | GPT-5.5 Pro | Winner |
|---|---|---|---|
| Intelligence | 55.7 | — | Tie |
| Output speed | 62 t/s | — | Tie |
| Output price | $25.00/1M | $180.00/1M | Claude Opus 4.8 |
| Context | 1000K | 1050K | GPT-5.5 Pro |
| Params | — | — | Tie |
| Provider | Anthropic | OpenAI | Tie |
Detailed analysis
Context Window
Winner: GPT-5.5 ProGPT-5.5 Pro provides 1,050,000 tokens versus Claude Opus 4.8's 1,000,000 tokens. This gives GPT-5.5 Pro a slight edge for the longest inputs. Both handle million-scale contexts effectively per their listed strengths.
Pricing
Winner: Claude Opus 4.8Claude Opus 4.8 costs $25 per million output tokens while GPT-5.5 Pro costs $180 per million. Claude is over seven times cheaper on output. This makes Claude the clear choice for cost-sensitive workloads.
Speed
Winner: Claude Opus 4.8Claude Opus 4.8 lists a concrete output speed of 60.93 tokens per second. GPT-5.5 Pro speed is unspecified. Claude therefore holds the measurable speed advantage based on available data.
Multimodal Capabilities
Winner: TieBoth models emphasize strong integration of text, images, and files with no audio or video support. GPT-5.5 Pro highlights seamless integration while Claude stresses effective handling of long multimodal inputs. Strengths are comparable within the given facts.
Claude Opus 4.8
Pros
- +Handles extremely long inputs effectively
- +Strong multimodal integration of text, images, and files
- +Careful and nuanced reasoning
Cons
- –Higher latency on large contexts
- –Conservative response style due to safety tuning
- –May require explicit guidance for creative tasks
GPT-5.5 Pro
Pros
- +Very large context window
- +Native support for files, images, and text
- +Seamless multimodal integration
Cons
- –High resource use with maximum context
- –No audio or video modalities
- –Potential latency on very long inputs
Summary: Claude Opus 4.8 vs GPT-5.5 Pro
Select GPT-5.5 Pro when maximum context size and seamless file-image-text handling outweigh cost. Select Claude Opus 4.8 when lower price, documented speed, and safety-tuned reasoning on long inputs are priorities. The models are closely matched on core multimodal context features but diverge sharply on economics and measurable performance.
Frequently asked questions
It depends: GPT-5.5 Pro for largest context and seamless integration, Claude Opus 4.8 for price and speed on similar context sizes.