MMODELYST
Models/GPT-5.3 Codex
MDL

GPT-5.3 Codex

OpenAI

Verified against Artificial Analysis · Jul 13, 2026
Capability
94
percentile index
Price /M
$1.75 / $14
in / out
Context
400K
tokens
Avg score
67.6
7 benchmarks
AA Intelligence
44.3
index
Speed
99 tok/s
TTFT 54s
Released
Feb 5, 2026
About

GPT-5.3 Codex is a proprietary model in the GPT family from OpenAI. Benchmarked on 7 evals, averaging 67.6.

Benchmark scores · 7
avg 67.6 — higher is better
GPQA Diamond
91.5
τ²-bench
86
IFBench
75.4
AA Long-Context Reasoning
74
SciCode
53.2
Terminal-Bench Hard
53
Humanity's Last Exam
39.9
Details
PublisherOpenAI
FamilyGPT
Parameters
License
WeightsClosed
ReleasedFeb 5, 2026
Performance & price
Output speed99 tok/s
Latency (TTFT)54s
Price in / out$1.75 / $14 per 1M
Blended price$4.81 / 1M

Median across API providers, via Artificial Analysis. Blended = 3:1 input:output. For reasoning models, latency includes thinking time. Methodology →

Capability over time

Append-only ledger — every observed change to this model's numbers.

API providers
Artificial Analysis$14/M