Claude Opus 4.8 vs GPT-5.5

Pick two tools from the same category to compare side-by-side.

	Claude Opus 4.8 Anthropic's Opus-tier model (May 2026) with improved coding, agentic, and honesty behavior over Opus 4.7.	GPT-5.5 OpenAI's flagship frontier model, positioned as a new class of intelligence for coding and professional work.
Category	model	model
Vendor type	commercial	commercial
Pricing	usage	usage
Strengths	+ Vendor-reported gains on coding and agentic benchmarks (Terminal-Bench 2.1, 84% on Online-Mind2Web) + Improved honesty; more likely to acknowledge missing information and flag flaws in its own code + Standard pricing unchanged from Opus 4.7 ($5 input / $25 output per million tokens), with a cheaper fast mode than before	+ OpenAI's recommended model for complex reasoning and coding + 1M-token context window with up to 128K output tokens + Generally available via the OpenAI API with listed pricing of $5 input / $30 output per million tokens
Tradeoffs	− Superseded as Anthropic's top model by Claude Fable 5 (June 2026) for the most demanding long-horizon work − API-only commercial model; no open weights	− Most expensive tier in OpenAI's lineup; GPT-5.4 is positioned as the more affordable option for similar work − API-only commercial model; no open weights
Used in stacks	0	0