GPT-5.1 Codex

by OpenAI

GPT-5.1 Codex from OpenAI — text model on the Opper gateway.

Key info

Input
Output
Features
Context window
272K
Max output
128K
Input price
$1.25 /1M
Output price
$10.00 /1M
  • US residency available
  • Zero data retention via Enterprise
  • No training by default
  • GDPR DPA available

Benchmarks

Independent benchmark scores — composite indices for reasoning, coding, and math, plus individual eval scores where available.

Global rank#59 of 518 LLMs
TierStrong
Output speed190 tok/s
First token5.88s
Intelligence Index43.1
Coding Index36.6
Math Index95.7
MMLU-Pro
86%
GPQA Diamond
86%
Humanity's Last Exam
23%
LiveCodeBench
85%
SciCode
40%
AIME 2025
96%
IFBench
70%
Long-context reasoning
67%
Terminal-Bench Hard
35%
τ²-Bench Telecom
83%

Available routes

GPT-5.1 Codex runs on 1 route through the Opper gateway. Compare residency, ZDR, and training posture at a glance — full data-handling detail per route below.

ProviderRegionZero data retentionTrainingInputOutput
OpenAIUSEnterpriseNo$1.25$10.00

Training posture across routes: No training on prompts by default.

Data handling per route

Each route hosting GPT-5.1 Codex has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.

OpenAI United States🇺🇸

Zero data retention is available via Opper Enterprise contract. No training on customer data. US; SCCs; DPA available.

Zero data retention
Available via Opper Enterprise contract.
Training
No training on customer data.
Logging
Abuse monitoring (30-day retention)
Third-party access
None disclosed
GDPR DPA
DPA available
Transfer mechanism
SCCs

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GPT-5.1 Codex by OpenAI — pricing, benchmarks | Opper AI