OpenAI GPT-5.6 Luna VS xAI Grok 4.20
Decision Recommendation
👑 Editorial Verdict: GPT-5.6 Luna strictly dominates Grok 4.20 across all compared dimensions. It is not only more cost-effective (blended cost of $2.25 vs $3.00 per 1M tokens) but also delivers superior coding accuracy (62.7% vs 51.8% on SWE-bench). Unless you have platform lock-in, GPT-5.6 Luna is the clear and optimal choice for all development workloads.
Was this recommendation helpful?
Model Specs
GPT-5.6 Luna
Benchmarks & Scores
Coding (swe-bench-pro)Winner (+10.9%)
62.7%excellent at multi-file repositories, autonomous agents, and industrial codebases
Reasoning (gpqa-diamond)Winner (+2.3%)
92.3%graduate-level science QA
Cost & Performance
Cost (per 1M tokens)1.3x cheaper
$2.25Input: $1.00 | Output: $6.00Context WindowLarger
1.05M tokensModel Specs
Grok 4.20
Benchmarks & Scores
Coding (swe-bench-pro)
51.8%excellent at multi-file repositories, autonomous agents, and industrial codebases
Reasoning (gpqa-diamond)
90%graduate-level science QA
Cost & Performance
Cost (per 1M tokens)
$3.00Input: $2.00 | Output: $6.00Context Window
1M tokensFrequently Asked Questions about GPT-5.6 Luna vs Grok 4.20 comparison
GPT-5.6 Luna is cheaper than Grok 4.20. GPT-5.6 Luna has a blended cost of $2.25/1M tokens, which is about 1.3x cheaper than Grok 4.20 at $3.00/1M tokens.
GPT-5.6 Luna is better for coding tasks on this benchmark. It scores 62.7% on swe-bench-pro (excellent at multi-file repositories, autonomous agents, and industrial codebases) compared to Grok 4.20 which scores 51.8%.
Related Matchups
Explore similar comparisons for GPT-5.6 Luna and Grok 4.20.