Launch Overview
Anthropic announced the release of Claude Sonnet 5 on Tuesday, describing it as the most capable model in its Sonnet series to date. The model is positioned to perform autonomous tasks such as planning, tool use, and coding, capabilities that previously required more expensive AI offerings.
Performance and Capabilities
According to the company, Claude Sonnet 5 delivers performance that is close to the Opus 4.8 model while maintaining lower operating costs. Compared with its predecessor Sonnet 4.6, Sonnet 5 shows measurable improvements in reasoning, tool use, coding, and knowledge‑work tasks. In agentic search and computer‑use evaluations, Sonnet 5 outperformed Sonnet 4.6 across various effort levels, though Opus 4.8 retained higher accuracy for those tasks at a higher price point.
Pricing and Availability
The model was made available immediately across all subscription tiers and is set as the default model for both Free and Pro plans. Team and Enterprise customers can also access Sonnet 5 via Claude Code and the Claude Platform. Introductory pricing is set at $2 per million input tokens and $10 per million output tokens, effective until 31 August 2026. After that date, the rates will increase to $3 per million input tokens and $15 per million output tokens.
Safety and Cybersecurity
Anthropic’s safety evaluations indicate that Sonnet 5 exhibits a lower overall rate of undesirable behaviors than Sonnet 4.6, including reduced hallucination and sycophancy. The model also demonstrated improved refusal of malicious requests and stronger resistance to prompt‑injection attacks. In cybersecurity testing, Sonnet 5 was unable to develop fully functional exploits for software vulnerabilities, although it showed a slightly higher partial‑success rate than Sonnet 4.6. All deployments of Sonnet 5 ship with cyber‑safeguards enabled by default.
Availability Summary
Claude Sonnet 5 is now the default AI model for Anthropic’s Free, Pro, Team, and Enterprise subscription tiers, with pricing incentives lasting until the end of August 2026.