Codex CLI Model Reference
Last updated: 2026-02-21
Current Models
| Model | ID | Released | Description |
|---|---|---|---|
| GPT-5.3-Codex | gpt-5.3-codex |
Feb 5, 2026 | Latest generation. 25% faster than 5.2. Self-bootstrapped (trained partly on its own output). SOTA on SWE-Bench Pro. Default model in ~/.codex/config.toml. |
| GPT-5.3-Codex Spark | gpt-5.3-codex-spark |
Feb 5, 2026 | Lightweight variant of 5.3. Near-instant responses. Pro subscribers only. Ideal for quick reads, small reviews, fast iteration. |
| GPT-5.2-Codex | gpt-5.2-codex |
Dec 2025 | Previous generation. Still fully supported. Use when 5.3 exhibits regressions on specific tasks or when reproducibility with older results matters. |
Deprecated Models
These model IDs no longer work with Codex CLI. Use the current equivalents above.
| Deprecated ID | Era | Replaced By |
|---|---|---|
o3 |
Mid-2025 | gpt-5.3-codex |
o3-mini |
Mid-2025 | gpt-5.3-codex-spark |
o4-mini |
Late 2025 | gpt-5.3-codex-spark |
codex-mini |
Early 2025 | gpt-5.3-codex-spark |
codex-5.2 |
Alias | gpt-5.2-codex |
gpt-5.1-codex-mini |
Oct 2025 | gpt-5.3-codex-spark |
gpt-5.1-codex-max |
Oct 2025 | gpt-5.3-codex |
Configuration
Default model is set in ~/.codex/config.toml:
model = "gpt-5.3-codex"
Override per-invocation with --model:
codex exec --model gpt-5.3-codex-spark "Quick review of auth.ts"
codex exec --model gpt-5.2-codex "Compare against previous results"
Both codex-orchestrator and codex-cto skills pass --model through to codex exec. Any model ID that Codex CLI accepts will work.
Selection Guide
| Task | Recommended Model | Why |
|---|---|---|
| Default for all tasks | gpt-5.3-codex |
Best balance of speed and capability |
| Quick reads, fast iteration | gpt-5.3-codex-spark |
Near-instant, low cost |
| Reproducing older results | gpt-5.2-codex |
Same model that produced original output |
| CTO planning (codex-cto) | gpt-5.3-codex |
Architectural reasoning benefits from full capability |
| CTO review (codex-cto) | gpt-5.3-codex |
Diff analysis needs full capability |
| One-shot subagent (codex-orchestrator) | gpt-5.3-codex |
Default |
| Quick researcher query | gpt-5.3-codex-spark |
Read-only, speed matters |