ClaudevsGPT

Claude Sonnet 4.5 vs GPT 5.6 Luna

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

Pricing

Side-by-side pricing

Claude Sonnet 4.5

Mid-tier

GPT 5.6 Luna

Fast / Budget
Input $/MTok
$3.00
$0.20
Output $/MTok
$15.00
$1.20
Cache discount
90% off
90% off
Context
200K
922K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
0
vs
70
Code Review
0
vs
68
Summarization
0
vs
84
Q&A
0
vs
85
Extraction
0
vs
89
Reasoning
0
vs
63
Classification
0
vs
91
Creative Writing
0
vs
58
Claude Sonnet 4.5
GPT 5.6 Luna

Guidance

When to use Claude Sonnet 4.5 vs GPT 5.6 Luna

Choose Claude Sonnet 4.5 when...

  • Similar performance; consider provider preference or ecosystem fit.

Choose GPT 5.6 Luna when...

  • -Cost matters: 93% cheaper on input tokens
  • -You need a larger context window (922K vs 200K)

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
Claude Sonnet 4.5
GPT 5.6 Luna
100K tokens
$0.66
$0.05Cheaper
1M tokens
$6.60
$0.82Cheaper
10M tokens
$66.00
$8.20Cheaper

FAQ

When should I use Claude Sonnet 4.5 instead of GPT 5.6 Luna?

Claude Sonnet 4.5 and GPT 5.6 Luna perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is GPT 5.6 Luna cheaper than Claude Sonnet 4.5?

Yes. GPT 5.6 Luna input costs $0.20/MTok vs $3.00/MTok for Claude Sonnet 4.5, saving 93% on input.

What are the context window sizes for Claude Sonnet 4.5 and GPT 5.6 Luna?

Claude Sonnet 4.5 has a 200K 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.