Model Comparator

Compare up to four models using the same criteria.

GPT-5.6 Luna (High)
OpenAI
GPT-5.3 Codex (Xhigh)
OpenAI

Differences only

✓ Best published value among measured models. — Data unavailable. These metrics do not establish an overall ranking.

Model Comparator
Metrics	GPT-5.6 Luna (High) OpenAI	GPT-5.3 Codex (Xhigh) OpenAI
Intelligence	32.1	Best: 32.5
Coding	63.3	—
Agentic	34.6	—
Speed	Best: 115 t/s	98.5 t/s
TTFT	Best: 16.9 s	71.5 s
Input · $ / 1M tokens	Best: $0.20	$1.75×8.8 relative to the lowest price among the compared models
Output · $ / 1M tokens	Best: $1.20	$14×11.7 relative to the lowest price among the compared models
Context window	Best: 1M	400K
Reasoning	Yes	Yes
Open weights	No	No
Cost / task	$0.044	—

Intelligence

GPT-5.6 Luna (High): 32.1
GPT-5.3 Codex (Xhigh): Best: 32.5

Coding

GPT-5.6 Luna (High): 63.3
GPT-5.3 Codex (Xhigh): —

Agentic

GPT-5.6 Luna (High): 34.6
GPT-5.3 Codex (Xhigh): —

Speed

GPT-5.6 Luna (High): Best: 115 t/s
GPT-5.3 Codex (Xhigh): 98.5 t/s

TTFT

GPT-5.6 Luna (High): Best: 16.9 s
GPT-5.3 Codex (Xhigh): 71.5 s

Input · $ / 1M tokens

GPT-5.6 Luna (High): Best: $0.20
GPT-5.3 Codex (Xhigh): $1.75×8.8 relative to the lowest price among the compared models

Output · $ / 1M tokens

GPT-5.6 Luna (High): Best: $1.20
GPT-5.3 Codex (Xhigh): $14×11.7 relative to the lowest price among the compared models

Context window

GPT-5.6 Luna (High): Best: 1M
GPT-5.3 Codex (Xhigh): 400K

Reasoning

GPT-5.6 Luna (High): Yes
GPT-5.3 Codex (Xhigh): Yes

Open weights

GPT-5.6 Luna (High): No
GPT-5.3 Codex (Xhigh): No

Cost / task

GPT-5.6 Luna (High): $0.044
GPT-5.3 Codex (Xhigh): —

Each reasoning level remains a separate configuration.

Score and cost

Each line joins the reasoning levels of a compared model; the large point marks the configuration in the table. The top-right corner holds the best score for the lowest cost. Select another point to compare that level.

GPT-5.6 Luna (High)32.1 · $0.45
GPT-5.3 Codex (Xhigh)32.5 · $4.81