The AI coding landscape has dramatically evolved in 2025, with both Anthropic's Claude Code and OpenAI's revamped Codex offering compelling but fundamentally different approaches to AI-assisted development. After OpenAI's surprising discontinuation of the original Codex in 2023, the company has returned with a completely reimagined system, while Claude Code has solidified its position as a premier development partner. Let's dive into the definitive comparison for 2025.
The Great Comeback: OpenAI Codex Returns
Before we compare, it's crucial to understand that the OpenAI Codex available in 2025 is completely different from the original 2021 version that was deprecated in March 2023. The new Codex isn't just a model—it's a full autonomous software engineering agent powered by codex-1, a specialized version of OpenAI's o3 model optimized for software engineering tasks.