OpenAI Codex

OpenAI
class A live

OpenAI's 2025 agentic coding product: Apache-2.0 CLI plus cloud agent and IDE, powered by GPT-5.x; free tier plus paid plans.

Layer 1 — factual axes

Pricing Free · Go $8/mo · Plus $20/mo · Pro $100–200/mo · API usage-based official source ↗ 2026-07-04
Model own (GPT-5.5 / GPT-5.4 / GPT-5.4 mini) official source ↗ 2026-07-04
Agentic yes official source ↗ 2026-07-04
Open source open · Apache-2.0 (CLI only; cloud/models closed) official source ↗ 2026-07-04
Form cloud agent (+ CLI + IDE) official source ↗ 2026-07-04
Free tier limited official source ↗ 2026-07-04

Layer 2 — output quality

No independent measure yet. We publish a quality figure only when a named external benchmark ranks this model — we don’t invent one.

Eligible for Best freeOpen-sourceAgentic

OpenAI’s 2025 agentic coding product: Apache-2.0 CLI plus cloud agent and IDE, powered by GPT-5.x; free tier plus paid plans.

Data as of 2026-07-04 · verified 2026-07-04. One ruler for all tools. How we measure ↗