ChatGPT is OpenAI's consumer and business AI product, powered by the GPT model family. GPT-5.6 is the current generation for advanced reasoning, coding, computer use, and professional work.
ChatGPT launched in November 2022 on GPT-3.5 and later added GPT-4, GPT-4o, the o-series reasoning models, and GPT-5. OpenAI released GPT-5.6 in July 2026 across ChatGPT, Codex, and the API. The generation includes the flagship Sol tier, the balanced Terra tier, and the fast, cost-efficient Luna tier. GPT-5.5 Instant remains available for fast everyday conversations, while GPT-5.6 powers higher-effort reasoning options on eligible plans.
Further reading
Claude is Anthropic's family of safety-focused language models for coding, agents, reasoning, and knowledge work. Claude Opus 5 is the current Opus generation.
Claude is Anthropic's flagship model family and was originally trained using the company's Constitutional AI feedback method. Anthropic introduced the Claude 3 Haiku, Sonnet, and Opus tiers in 2024, added extended thinking with Claude 3.7 in 2025, and launched the Claude 4 generation for coding and agent workflows in May 2025. Claude Opus 5, released in July 2026, adds a one-million-token context window, thinking by default, deeper test-time reasoning, and stronger long-horizon coding, multi-agent, vision, and enterprise-work capabilities.
Further reading
ChatGPT
Claude