GPTvsGPT

GPT 5.4 vs GPT 5.6 Luna

Side-by-side comparison of pricing, task quality, and projected cost at higher scale.

Pricing

Side-by-side pricing

GPT 5.4

Mid-tier

GPT 5.6 Luna

Fast / Budget
Input $/MTok
$2.50
$0.20
Output $/MTok
$15.00
$1.20
Cache discount
90% off
90% off
Context
1.1M
922K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
63
vs
62
Code Review
82
vs
68
Summarization
67
vs
57
Q&A
91
vs
85
Extraction
76
vs
74
Reasoning
88
vs
86
Classification
88
vs
91
Creative Writing
79
vs
69
GPT 5.4
GPT 5.6 Luna

Guidance

When to use GPT 5.4 vs GPT 5.6 Luna

Choose GPT 5.4 when...

  • -You need strong q&a (confidence 91 vs 85)
  • -You need strong reasoning (confidence 88 vs 86)
  • -You need strong code review (confidence 82 vs 68)
  • -You need strong creative writing (confidence 79 vs 69)
  • -You need a larger context window (1.1M vs 922K)

Choose GPT 5.6 Luna when...

  • -You need strong classification (confidence 91 vs 88)
  • -Cost matters: 92% cheaper on input tokens

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
GPT 5.4
GPT 5.6 Luna
100K tokens
$0.63
$0.05Cheaper
1M tokens
$10.25
$0.82Cheaper
10M tokens
$102.50
$8.20Cheaper

FAQ

When should I use GPT 5.4 instead of GPT 5.6 Luna?

GPT 5.4 outperforms GPT 5.6 Luna for Code Generation, Code Review, Summarization. It costs $2.50/$15.00 per million tokens (input/output).

Is GPT 5.6 Luna cheaper than GPT 5.4?

Yes. GPT 5.6 Luna input costs $0.20/MTok vs $2.50/MTok for GPT 5.4, saving 92% on input.

What are the context window sizes for GPT 5.4 and GPT 5.6 Luna?

GPT 5.4 has a 1.1M token context window. GPT 5.6 Luna has a 922K token context window.

Track your real costs

Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.