OpenAI / openai/gpt-5.3-codex
GPT-5.3-Codex - access through LLMTR
Targets repo-scale understanding, long edit chains, and demanding agentic coding workflows. One of the most ambitious Codex options for teams building coding products.
Technical specifications
| Canonical ID | openai/gpt-5.3-codex |
|---|---|
| Provider | OpenAI |
| Context window | 400,000 tokens |
| Operations | RESPONSES |
| Modalities | text, image |
Pricing
A 6% platform margin applies to credit top-ups; model usage prices are not separately marked up.
| Operation | Metric | Unit | Price |
|---|---|---|---|
| RESPONSES | INPUT_TEXT | PER_1M_TOKENS | $1.75 |
| RESPONSES | CACHE_READ | PER_1M_TOKENS | $0.175000 |
| RESPONSES | OUTPUT_TEXT | PER_1M_TOKENS | $14.00 |
Example usage
With existing OpenAI SDK flows, change only the base URL and model identifier.
curl https://llmtr.com/v1/chat/completions \
-H "Authorization: Bearer llmtr-your_key" \
-H "Content-Type: application/json" \
-d '{"model":"openai/gpt-5.3-codex","messages":[{"role":"user","content":"Hello"}]}'