token.app โ€บ Compare โ€บ o3 vs Grok 4.5

o3 vs Grok 4.5

Grok 4.5 leads on 3 of 3 shared benchmarks. Grok 4.5 is 1.2ร— cheaper per token on a blended 3:1 basis. Grok 4.5 accepts the larger context window (500K).

Head to head
Blended price uses a 3:1 input:output mix
o3Grok 4.5
ProviderOpenAIxAI
Input $/1M$2.00$2.00
Output $/1M$8.00$6.00
Blended $/1M$3.50$3.00
Context window200K500K
Max output100Kโ€”
ReleasedApr 2025Jul 2026
LicenceProprietaryProprietary
GPQA Diamond 81.8% 93.4%
SimpleQA Verified 53.0% 53.5%
OTIS Mock AIME 84.4% 97.8%
Benchmark scores independently run and published by Epoch AI, 'AI Benchmarking Hub', used under CC BY 4.0. Only benchmarks with a score for BOTH models are compared.
Choose o3 ifโ€ฆ
  • No clear advantage on the data we hold.
Choose Grok 4.5 ifโ€ฆ
  • Costs less per token โ€” $3.00 vs $3.50 blended
  • Higher GPQA Diamond (93.4% vs 81.8%)
  • Higher SimpleQA Verified (53.5% vs 53.0%)
  • Higher OTIS Mock AIME (97.8% vs 84.4%)
  • Larger context window (500K)
  • Newer model (released Jul 2026)
FAQ
Which is better, o3 or Grok 4.5?
Across the 3 benchmarks both models have independently-run scores for, o3 leads on 0 and Grok 4.5 leads on 3. Benchmarks are one input โ€” price and context window are on this page too.
Is o3 cheaper than Grok 4.5?
Grok 4.5 is cheaper: $3.00 versus $3.50 per million tokens blended at 3:1 input:output. Input alone: $2.00 vs $2.00. Output alone: $8.00 vs $6.00.
What context windows do o3 and Grok 4.5 have?
o3: 200,000 tokens. Grok 4.5: 500,000 tokens.
Who makes o3 and Grok 4.5?
o3 is made by OpenAI. Grok 4.5 is made by xAI.
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