GPT-5.3 Codex
GPT-5.3 Codex via Azure OpenAI
ToolsStructured output
Context window
272K
Max output
128K
Input price
$1.75 /1M
Output price
$14.00 /1M
Benchmarks
Independent benchmark scores — composite indices for reasoning, coding, and math, plus individual eval scores where available.
Intelligence Index53.6
Coding Index53.1
GPQA Diamond
92%
Humanity's Last Exam
40%
SciCode
53%
IFBench
75%
Long-context reasoning
74%
Terminal-Bench Hard
53%
τ²-Bench Telecom
86%
See full leaderboard →Benchmarks via Artificial Analysis · View on AA
Available routes
The same GPT-5.3 Codex runs on 2 different routes through the Opper gateway. Each route has its own data-handling posture.
| Provider | Region | Zero data retention | Training | Logging | Contract | Input | Output |
|---|---|---|---|---|---|---|---|
| Azure OpenAI | EU | Opt-in | No | Up to 30 days for abuse monitoring | EA/MCA-E | $1.75 | $14.00 |
| OpenAI | US | Opt-in | No (opt-in) | Up to 30 days for abuse monitoring on stateless endpoints. Stateful endpoints (Conversations, ChatKit, Vector Stores) retain until deleted. | Enterprise | $1.75 | $14.00 |
Human review: Abuse-flagged only