BenchLeader

GPT-6 Sol vs Grok 4.20

Verdict
  • GPT-6 Sol (max) leads on quality: 67.7 vs 59.6.
  • GPT-6 Sol (max) is stronger in composite, knowledge, long context, multimodal, reasoning.
  • Grok 4.20 (thinking) is stronger in agents & tools, coding, human preference, instruction following, maths.
  • Grok 4.20 (thinking) is 2.6× cheaper ($1.56 vs $4.00 per 1M blended).
MetricGPT-6 Sol (max)Grok 4.20 (thinking)
BenchLeader Index67.759.6
Composite score86.259.9
Knowledge score75.456.6
Long context score67.760.1
Multimodal score67.159.5
Reasoning score95.060.4
Agents & tools score51.6
Coding score54.7
Human preference score67.2
Instruction following score79.9
Maths score55.5
Blended price $/M$4.00$1.56
Output speed126 tok/s106 tok/s
Time to first answer107.2 s23.9 s
Context window1.1M2M
GPQA Diamond89.3%
FrontierMath Tiers 1–344.9%
FrontierMath Tier 417.1%
OTIS Mock AIME92.2%
SimpleQA Verified30.2%
ProofBench14.0%
LMArena Text1472
LMArena Hard Prompts1488
LMArena Coding1510
LMArena WebDev1374
LMArena Vision1263
AA Intelligence Index47.525.7
IFBench82.9%
AA-LCR83.7%69.0%
MMMU-Pro83.3%74.6%
AA-Omniscience27.114.8
Terminal-Bench Hard40.9%
GPQA Diamond (AA)91.1%
Humanity's Last Exam (AA)47.9%34.5%
SciCode (AA)57.6%
τ²-Bench Telecom (AA)96.5%
AIME (Vals)96.5%
LiveCodeBench84.3%
MMLU-Pro86.3%
LegalBench77.7%
CorpFin63.7%
TaxEval74.1%
MedQA94.5%
Terminal-Bench 2.1 (Vals)44.2%
SWE-bench (Vals)72.2%
GPQA Diamond (Vals)88.6%
Vals Index17.6
Kagi LLM Benchmark75.0%
ARC-AGI-189.5%
ARC-AGI-265.1%
ARC-AGI-30.1%
CritPt30.9%6.6%
GDPval (AA)49.4%
APEX-Agents (AA)14.2%
CaseLaw v254.5%
Code Migration0.3%
Excel Modeling Benchmark11.7%
Finance Agent v228.5%
Harvey's Legal Agent Benchmark0.0%
Legal Research Bench13.9%
MedCode32.2%
MedScribe63.4%
MMMU-Pro (Vals)83.5%
MortgageTax45.4%
SAGE38.2%
Terminal-Bench 2.0 (Vals)40.5%
Vals Multimodal Index39.1%
Vibe Code Bench v1.14.1%
LMArena Maths1467
LMArena Creative Writing1446
LMArena Instruction Following1445
LMArena Multi-turn1480
LMArena Longer Queries1465
LMArena Document1439
Chess Puzzles24.0%
ForecastBench60.7%
Terminal-Bench 4.0 (AA)43.9%
AutomationBench61.6%
GDP.pdf24.8%
MLCR16.1%
AA-Omniscience: accuracy54.5%28.9%
AA-Omniscience: non-hallucination39.9%82.6%
AA-Briefcase1483

Data as of 2026-09-23. Best configuration of each model; every score links to its source on the model pages.

GPT-6 Sol vs Grok 4.20: questions

Is GPT-6 Sol better than Grok 4.20?
GPT-6 Sol (max) leads on quality: 67.7 vs 59.6. The BenchLeader Index combines every independent quality benchmark; GPT-6 Sol (max) is ahead overall as of 2026-09-23, but check the category scores for your use.
Which is cheaper, GPT-6 Sol or Grok 4.20?
Grok 4.20 is cheaper: $1.56 against $4.00 per million tokens, blended at three input tokens per output token.
Which is faster, GPT-6 Sol or Grok 4.20?
GPT-6 Sol streams faster: 126 against 106 output tokens per second.
Which has the larger context window?
Grok 4.20 accepts more context: 2M against 1.1M tokens.