o3 vs Grok 4.20
Pricing, context window, and benchmark comparison · Last updated April 2026
Grok 4.20 is cheaper than o3 at $2.00/1M/1M vs $2.00/1M/1M input tokens. o3 scores higher on quality benchmarks (ELO 1395). Choose Grok 4.20 for cost-sensitive workloads; choose o3 for maximum quality.
Which is cheaper: o3 or Grok 4.20?
o3 and Grok 4.20 are identically priced at $2.00/1M per 1M input tokens. Output pricing follows a similar pattern: o3 charges $8.00/1M/1M vs $6.00/1M/1M for Grok 4.20.
Which has better quality: o3 or Grok 4.20?
Based on LMSYS Chatbot Arena rankings, o3 achieves a higher ELO score (1395 vs 1380), suggesting stronger performance on open-ended tasks. o3 excels at top-tier reasoning on math, science, and agentic tasks. Grok 4.20 is known for 2m token context window — tied for largest available.
Which should you choose: o3 or Grok 4.20?
- → Top-tier reasoning on math, science, and agentic tasks
- → 87% cheaper than original o1 at the same capability tier
- → 200K context window
- → 2M token context window — tied for largest available
- → Real-time X (Twitter) data access
- → Strong reasoning and multi-agent variants
Frequently Asked Questions
Which is cheaper: o3 or Grok 4.20?
o3 and Grok 4.20 have the same input price of $2.00/1M per 1M tokens.
Which has better quality: o3 or Grok 4.20?
o3 scores higher on the LMSYS Chatbot Arena with an ELO of 1395, suggesting better overall quality for most tasks.
Which has a larger context window: o3 or Grok 4.20?
Grok 4.20 has a larger context window at 2000K tokens.
Should I choose o3 or Grok 4.20?
Choose Grok 4.20 if cost is the priority. Choose o3 if benchmark quality is most important. Consider your specific use case: o3 is best for reasoning and math, while Grok 4.20 excels at reasoning and research.
Is o3 or Grok 4.20 open source?
o3 is proprietary. Grok 4.20 is proprietary.