GPT-5.2-Codex vs Grok-4-Fast-Reasoning
Grok-4-Fast-Reasoning is cheaper on output tokens, while Grok-4-Fast-Reasoning offers a larger context window. Choose GPT-5.2-Codex or Grok-4-Fast-Reasoning based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | GPT-5.2-Codex | Grok-4-Fast-Reasoning |
|---|---|---|
| Provider | Poe | Poe |
| Input / 1M tokens | $1.60 | $0.20 |
| Output / 1M tokens | $13.00 | $0.50 |
| Context window | 400K | 2M |
| Parameters | — | — |
| Open weights | No | No |
| Released | Jan 2026 | Sep 2025 |
FAQ
Is GPT-5.2-Codex or Grok-4-Fast-Reasoning cheaper?
Grok-4-Fast-Reasoning is cheaper on output tokens ($0.50 vs $13.00 per 1M).
Which has the larger context window, GPT-5.2-Codex or Grok-4-Fast-Reasoning?
Grok-4-Fast-Reasoning has the larger context window (2M tokens).
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.