The previous frontier champion, now overshadowed by 4.6 but still incredibly capable. Opus 4.5 scored 80.9% on SWE-bench and delivers top-tier creative writing. At the same price as 4.6, there's little reason to choose it over the newer model unless you have specific version-pinning needs.
“Still a beast, but 4.6 has taken its crown. Use for version stability.”
Teams with existing 4.5 integrations that aren't ready to migrate.
Training data policy: API data NOT used for training by default
DPDP Act (India): Data processed in US. No India data center. Compliant via DPA.
Data residency: US
Available. API accessible from India. Payments via international card. Also on AWS Bedrock (Mumbai).