Compare models
Put models side by side on price, context, capabilities, and benchmarks.
GPT-6 Luna is the fast, low-cost tier of OpenAI's GPT-6 series (1.05M-token context, text, image, and file input, $0.10/$0.50 per million input/output tokens), released September 22, 2026 below GPT-6 Sol and the flagship GPT-6 Astra. It is built for high-volume tasks with a clear goal, such as summarization, extraction, classification, quick questions, and lightweight agentic steps.
Claude Sonnet 5.5 is Anthropic's Sonnet-class model (1M-token context, 128K max output, $2/$10 per million input/output tokens), released September 28, 2026 as a direct upgrade to Sonnet 5 and a faster, lower-cost complement to Opus 5.5. It generates output over 30% faster with fewer tokens per task, and is strongest at well-scoped everyday work such as building features, fixing bugs, and producing polished documents, slides, and spreadsheets.
Benchmarks
Head-to-head scores across reasoning, coding, and agentic indices, plus per-domain rankings.
Intelligence
Coding
GPT-6 Luna has no data
Claude Sonnet 5.5 has no data
Automation & Tool Use
GPT-6 Luna has no data
Claude Sonnet 5.5 has no data
Intelligence, coding & agentic scores from Artificial Analysis.
Software & IT Services
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