Anthropic launched Claude Opus 4.8 on May 28, 2026 — just 41 days after Opus 4.7. The release is positioned as a significant quality-of-life update: faster responses, better long-context consistency, and a dramatic jump in mathematical reasoning.
Math benchmark: 69.3% to 96.7%
The most striking improvement is on USAMO 2026 — the USA Mathematical Olympiad benchmark. Opus 4.8 scores 96.7%, up from 69.3% on Opus 4.7. That is a 27-point jump in 41 days, making Opus 4.8 the strongest publicly available model on advanced mathematics.
Opus 4.8 is also roughly four times less likely to let flaws in its own code pass without flagging them, and proactively signals uncertainty rather than confidently hallucinating.
Dynamic Workflows in Claude Code
The biggest agentic feature is Dynamic Workflows: Claude Code can now plan a large task, spin up up to 1,000 parallel subagents, distribute the work across them, and verify outputs against your test suite — all without human intervention. The feature is designed for repository-scale migrations and hundreds-of-thousands-of-lines-of-code refactors that would previously require a team of engineers.
Pricing: same base, cheaper Fast mode
Standard pricing holds at $5 per million input tokens and $25 per million output tokens — identical to Opus 4.7. The big change is in Fast mode: it drops from $30/$150 per million tokens (Opus 4.7) to $10/$50 — a 3× cost reduction for latency-sensitive workloads. Prompt caching brings savings up to 90%; batch processing offers 50% off.
Opus 4.8 is available in Claude.ai for Pro, Max, Team, and Enterprise subscribers, and via the Anthropic API, AWS Bedrock, Google Cloud Vertex AI, and Microsoft Foundry.
Mythos Preview coming soon
Separately, Anthropic confirmed that Claude Mythos Preview — the restricted-access cybersecurity model — will be available to approved organizations "in the coming weeks." During its 30-day preview, Mythos and ~50 partner organizations identified more than 10,000 high- or critical-severity vulnerabilities in systemically important software.