o3 vs Claude Haiku 4.5
Pricing, context window, and benchmark comparison · Last updated April 2026
Claude Haiku 4.5 is cheaper than o3 at $1.00/1M/1M vs $2.00/1M/1M input tokens — a 2.0x cost difference. o3 scores higher on quality benchmarks (ELO 1395). Choose Claude Haiku 4.5 for cost-sensitive workloads; choose o3 for maximum quality.
Which is cheaper: o3 or Claude Haiku 4.5?
Claude Haiku 4.5 is the cheaper option at $1.00/1M per 1M input tokens, compared to $2.00/1M for o3. That is a 2.0x cost difference on input tokens. Output pricing follows a similar pattern: o3 charges $8.00/1M/1M vs $5.00/1M/1M for Claude Haiku 4.5.
Which has better quality: o3 or Claude Haiku 4.5?
Based on LMSYS Chatbot Arena rankings, o3 achieves a higher ELO score (1395 vs 1320), suggesting stronger performance on open-ended tasks. o3 excels at top-tier reasoning on math, science, and agentic tasks. Claude Haiku 4.5 is known for near-frontier intelligence at the lowest claude price tier.
Which should you choose: o3 or Claude Haiku 4.5?
- → Top-tier reasoning on math, science, and agentic tasks
- → 87% cheaper than original o1 at the same capability tier
- → 200K context window
- → Near-frontier intelligence at the lowest Claude price tier
- → Fastest Claude model
- → 200K context window
Frequently Asked Questions
Which is cheaper: o3 or Claude Haiku 4.5?
Claude Haiku 4.5 is cheaper at $1.00/1M per 1M input tokens, making it 2.0x more affordable.
Which has better quality: o3 or Claude Haiku 4.5?
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 Claude Haiku 4.5?
Both o3 and Claude Haiku 4.5 have the same context window.
Should I choose o3 or Claude Haiku 4.5?
Choose Claude Haiku 4.5 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 Claude Haiku 4.5 excels at fast-response and customer-support.
Is o3 or Claude Haiku 4.5 open source?
o3 is proprietary. Claude Haiku 4.5 is proprietary.