tokevenGPTvsGrok
GPT 5.6 Luna vs Grok 4.3
Side-by-side comparison of pricing, task quality, and projected cost at higher scale.
Pricing
Side-by-side pricing
GPT 5.6 Luna
Fast / BudgetGrok 4.3
Mid-tierInput $/MTok
$0.20
$1.25
Output $/MTok
$1.20
$2.50
Cache discount
90% off
84% off
Context
1,050K
1,000K
Quality
Task confidence comparison
Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
70
vs
0
Code Review
68
vs
0
Summarization
84
vs
0
Q&A
85
vs
0
Extraction
89
vs
0
Reasoning
63
vs
0
Classification
91
vs
0
Creative Writing
58
vs
0
GPT 5.6 Luna
Grok 4.3
Guidance
When to use GPT 5.6 Luna vs Grok 4.3
Choose GPT 5.6 Luna when...
- -Cost matters: 84% cheaper on input tokens
- -You need a larger context window (1,050K vs 1,000K)
Choose Grok 4.3 when...
- Similar performance; consider provider preference or ecosystem fit.
At scale
Cost at scale
Estimated cost assuming a seventy percent input and thirty percent output token split.
GPT 5.6 Luna
Grok 4.3
100K tokens
$0.05Cheaper
$0.16
1M tokens
$0.82Cheaper
$3.25
10M tokens
$8.20Cheaper
$32.50
FAQ
When should I use GPT 5.6 Luna instead of Grok 4.3?
GPT 5.6 Luna and Grok 4.3 perform similarly across all tracked tasks. Pick based on pricing and provider preference.
Is Grok 4.3 cheaper than GPT 5.6 Luna?
Grok 4.3 input costs $1.25/MTok, which is 525% more than GPT 5.6 Luna at $0.20/MTok.
What are the context window sizes for GPT 5.6 Luna and Grok 4.3?
GPT 5.6 Luna has a 1,050K token context window. Grok 4.3 has a 1,000K token context window.
Go deeper on either model
Per-call cost calculators, provider lineups, and price history for both models on this page.
Other comparisons
How GPT 5.6 Luna and Grok 4.3 stack up against the rest of the field.
Track your real costs
Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.