Standard Compute
Model comparison 2026

GPT-5.6 Luna vs GPT-6 Luna

GPT-5.6 Luna
OpenAI · Budget · Proprietary
$0.50/1M · 1.1M ctx
GPT-6 Luna
OpenAI · Budget · Proprietary
$0.22/1M · 1.1M ctx

Community vote

Pick a winner in each dimension. You can change your vote any time.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for money
How much capability you get per dollar
Reliability
Consistent results: fewer refusals, loops and format breaks

Specs and pricing side by side

Spec
GPT-5.6 Luna
GPT-6 Luna
Maker
OpenAI
OpenAI
Blended price / 1M
$0.50
$0.22
Input / output
$0.20 in · $1.20 out / 1M tokens
$0.10 in · $0.50 out / 1M tokens
Context window
1.1M
1.1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
8.4
8.7
Agentic Ability
8.3
8.5
Speed
9.3
9.3
Value for money
9.0
9.4
Reliability
9.1
9.1

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: GPT-5.6 Luna or GPT-6 Luna?

Updated 2026-10-13

Choose GPT-5.6 Luna if you want cheap, fast subtasks, routing, and subagents in OpenAI-based stacks. Choose GPT-6 Luna if you want cheap, fast subtasks, routing and subagents in OpenAI-based stacks.

In our editorial scoring, GPT-6 Luna leads in 3 of five dimensions (output quality, agentic ability and value for money), while GPT-5.6 Luna leads in 0. On price, GPT-5.6 Luna runs about $0.50 per 1M tokens (blended) and is proprietary; GPT-6 Luna is about $0.22 and proprietary.

Where GPT-5.6 Luna falls short
  • Clear quality step below Terra and Sol
  • Superseded by GPT-6 Luna, which is cheaper ($0.10/$0.50) and stronger
Full GPT-5.6 Luna breakdown →
Where GPT-6 Luna falls short
  • Weak on long agentic runs (16.4% on Terminal-Bench 4.0)
  • Clear quality step below GPT-6.1 Sol
Full GPT-6 Luna breakdown →

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