Rival AI labs OpenAI and Anthropic unveiled new models within hours of each other on September 22, escalating competition not just over AI performance but over the cost of putting increasingly powerful models to work. OpenAI launched GPT-6 Sol and GPT-6 Luna, two more affordable additions to its GPT-6 family, while Anthropic introduced Claude Opus 5.5, its latest high-end model focused heavily on coding, autonomous work and professional tasks.
GPT-6 Sol costs $2 per million input tokens and $10 per million output tokens through the API, while GPT-6 Luna costs $0.10 per million input tokens and $0.50 per million output tokens - a 50% reduction compared with promotional pricing for the corresponding GPT-5.6 models. OpenAI says Sol is positioned for complex coding and agentic workflows, while Luna targets focused, high-volume tasks.
Anthropic says Opus 5.5 performs at roughly the level of its larger Claude Fable 5.1 model on most tasks while costing 40% less to run on typical workloads than Opus 5, with output generation more than 30% faster. Safety is a major focus for both releases, which came after Anthropic's CEO publicly called for slowing the pace of frontier AI development.
The near-simultaneous launches underline a shift in the AI race: frontier models are becoming more capable, but the battle is increasingly about making that intelligence cheaper and practical to deploy at much larger scale.
