Anthropic Makes Claude Sonnet 5 Introductory Pricing Permanent
Anthropic has announced that the introductory pricing for Claude Sonnet 5 will remain permanent. The rates, originally set to expire on August 31, will stay at $2 per million input tokens and $10 per million output tokens. Making this pricing permanent lowers the long-term cost barrier for developers and enterprises building applications on Claude Sonnet 5. It also intensifies price competition among major LLM providers in the AI market. The pricing structure maintains a 5x cost difference between input and output tokens, reflecting the higher computational cost of generating sequential outputs. Claude Sonnet 5 is positioned as a highly capable model with agentic-coding strengths comparable to Opus-class models.
## BACKGROUND
Large language models (LLMs) process and generate text in units called tokens. API providers typically charge developers separately for input tokens (the prompt and context sent to the model) and output tokens (the generated response). Output tokens generally cost more because generating them requires sequential computation, which is more resource-intensive.