Which model is better: GPT-5.6 Luna or xAI Grok 4.6?

GPT-5.6 Luna is 91.0% cheaper for input tokens ($0.18 vs. $2.00 per 1M tokens) and $0.72 vs. $6.00 for output tokens (11.1x cost difference). In terms of operational performance, GPT-5.6 Luna delivers faster response latency with 90ms TTFT (190ms faster than xAI Grok 4.6). xAI Grok 4.6 leads coding benchmarks at 76.8% SWE-bench vs. 48.5% for GPT-5.6 Luna.
Verified daily via automated API latency tests and official documentation.

Verified Performance & Unit Economics Delta

Daily synchronized metrics from synthetic latency endpoints and benchmark evaluations.

Metric / Dimension GPT-5.6 Luna xAI Grok 4.6 Net Delta / Advantage
Input Cost / 1M Tokens $0.18 $2.00 GPT-5.6 Luna is 11.1x cheaper
Output Cost / 1M Tokens $0.72 $6.00 GPT-5.6 Luna (88% lower)
Avg TTFT Response Latency 90ms 280ms GPT-5.6 Luna (+190ms faster)
SWE-bench Verified (Coding) 48.5% 76.8% xAI Grok 4.6 (+28.3% lead)
Inference Value Score (IVR) 99.9 / 100 74.6 / 100 GPT-5.6 Luna (+25.3 pts)

Interactive Monthly Token Economics & ROI Forecaster

Model your expected production workload across prompt (input) and completion (output) tokens.

Live Calculation Engine
10.0M Tokens
100K 50M 250M 500M+
2.5M Tokens
100K 10M 50M 100M+

Estimated Monthly Spend

GPT-5.6 Luna $5.45

$0.18/1M in · $0.72/1M out

xAI Grok 4.6 $67.50

$2/1M in · $6/1M out

Projected Monthly Cost Reduction
$62.05 / mo
(91.9% lower cost)
A

When to Choose GPT-5.6 Luna

Choose GPT-5.6 Luna when you need Real-time conversational agents, high-volume classification, intent detection, and low-latency interactive apps. and have an infrastructure budget aligned with $0.18/1M tokens.

B

When to Choose xAI Grok 4.6

Choose xAI Grok 4.6 when you need Frontier real-time web & social intelligence, complex STEM proofs, competitive coding, and deep factual synthesis. and prioritize xAI ecosystem integration at $2.00/1M tokens.

Related Questions & Decision Factors

Which is cheaper: GPT-5.6 Luna or xAI Grok 4.6?

GPT-5.6 Luna is cheaper at $0.18/1M input tokens compared to $2.00/1M for xAI Grok 4.6.

Which model has lower latency: GPT-5.6 Luna or xAI Grok 4.6?

GPT-5.6 Luna delivers faster response times with an average TTFT of 90ms vs 280ms for xAI Grok 4.6.

When should you choose GPT-5.6 Luna?

Choose GPT-5.6 Luna when you need Real-time conversational agents, high-volume classification, intent detection, and low-latency interactive apps. and have an infrastructure budget aligned with $0.18/1M tokens.

When should you choose xAI Grok 4.6?

Choose xAI Grok 4.6 when you need Frontier real-time web & social intelligence, complex STEM proofs, competitive coding, and deep factual synthesis. and prioritize xAI ecosystem integration at $2.00/1M tokens.

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