Anthropic ships Claude Opus 4.8 at $5/$25 with cheaper fast mode
28 May 2026. Same list price as Opus 4.7. Fast mode $10/$50. System card: not past Mythos Preview on RSP. Prompt-injection tests vs 4.7 are mixed.
TLDR
Anthropic's 28 May 2026 post says Claude Opus 4.8 is available everywhere at $5 per million input tokens and $25 per million output tokens, unchanged from Opus 4.7. Fast mode is $10/$50 and described as 2.5 times the speed and three times cheaper than prior fast mode. AWS said the same day it is on Amazon Bedrock and Claude Platform on AWS. The Opus 4.8 system card says the model does not advance the capability frontier beyond Claude Mythos Preview under Anthropic's Responsible Scaling Policy, and that in some agentic tests it was "somewhat less robust than Opus 4.7" on prompt injection until safeguards were applied.