Custom Model vs GPT-5.3 Codex
Custom Model is cheaper on output tokens, while GPT-5.3 Codex offers a larger context window. Choose Custom Model or GPT-5.3 Codex based on the trade-off between cost, context, and the benchmarks that matter for your use case.
| Spec | Custom Model | GPT-5.3 Codex |
|---|---|---|
| Provider | LLM Gateway | LLM Gateway |
| Input / 1M tokens | $0.00 | $1.75 |
| Output / 1M tokens | $0.00 | $14.00 |
| Context window | 128K | 400K |
| Parameters | — | — |
| Open weights | No | No |
| Released | Jan 2024 | Feb 2026 |
FAQ
Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.