OpenAIGPT-5.5VSxAIGrok 4.20
Our Take
This matchup represents a clear tradeoff between peak intelligence and budget efficiency. GPT-5.5 is noticeably superior (holding a 5.2% average lead in benchmarks), but it carries a significant 3.8x price premium. Choose GPT-5.5 if you need top-tier reasoning or code debugging, but for high-volume pipelines, Grok 4.20 is the smarter business decision.
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Benchmarks & Scores
Coding (swe-bench-pro)Winner (+6.8%)
58.6%excellent at multi-file repositories, autonomous agents, and industrial codebases
Reasoning (gpqa-diamond)Winner (+3.6%)
93.6%graduate-level science QA
Cost & Context
Cost (per 1M tokens)
$11.25Input: $5.00 | Output: $30.00Context WindowLarger
1.05M tokensBenchmarks & 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 & Context
Cost (per 1M tokens)3.8x cheaper
$3.00Input: $2.00 | Output: $6.00Context Window
1.05M tokensFrequently Asked Questions about GPT-5.5 vs Grok 4.20
Grok 4.20 is cheaper than GPT-5.5. Grok 4.20 has a blended cost of $3.00/1M tokens, which is about 3.8x cheaper than GPT-5.5 at $11.25/1M tokens.
GPT-5.5 is better for coding tasks on this benchmark. It scores 58.6% on swe-bench-pro (excellent at multi-file repositories, autonomous agents, and industrial codebases) compared to Grok 4.20 which scores 51.8%.
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