Home/Compare/o3 vs o4-mini

o3 vs o4-mini

Pricing, context window, and benchmark comparison · Last updated April 2026

Quick Verdict

o4-mini is cheaper than o3 at $1.10/1M/1M vs $2.00/1M/1M input tokens — a 1.8x cost difference. o3 scores higher on quality benchmarks (ELO 1395). Choose o4-mini for cost-sensitive workloads; choose o3 for maximum quality.

Detailed Comparison

Metrico3o4-mini
Input Price / 1M tokens$2.00/1M$1.10/1MCheaper
Output Price / 1M tokens$8.00/1M$4.40/1MCheaper
Context Window200K200K
ELO Score (LMSYS)1395Smarter1350
Open Source
Free Tier
Release Date2025-042025-04

Which is cheaper: o3 or o4-mini?

o4-mini is the cheaper option at $1.10/1M per 1M input tokens, compared to $2.00/1M for o3. That is a 1.8x cost difference on input tokens. Output pricing follows a similar pattern: o3 charges $8.00/1M/1M vs $4.40/1M/1M for o4-mini.

Which has better quality: o3 or o4-mini?

Based on LMSYS Chatbot Arena rankings, o3 achieves a higher ELO score (1395 vs 1350), suggesting stronger performance on open-ended tasks. o3 excels at top-tier reasoning on math, science, and agentic tasks. o4-mini is known for cheapest reasoning model in the openai lineup.

Which should you choose: o3 or o4-mini?

Choose o3 if:
  • Top-tier reasoning on math, science, and agentic tasks
  • 87% cheaper than original o1 at the same capability tier
  • 200K context window
Choose o4-mini if:
  • Cheapest reasoning model in the OpenAI lineup
  • Strong performance on code and math for the price
  • 200K context window

Frequently Asked Questions

Which is cheaper: o3 or o4-mini?

o4-mini is cheaper at $1.10/1M per 1M input tokens, making it 1.8x more affordable.

Which has better quality: o3 or o4-mini?

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 o4-mini?

Both o3 and o4-mini have the same context window.

Should I choose o3 or o4-mini?

Choose o4-mini 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 o4-mini excels at reasoning and coding.

Is o3 or o4-mini open source?

o3 is proprietary. o4-mini is proprietary.

Related Comparisons

GPT-5.4 vs o3
GPT-5.4 vs o4-mini
Claude Opus 4.7 vs o3
Claude Opus 4.7 vs o4-mini
Gemini 3.1 Pro vs o3
Gemini 3.1 Pro vs o4-mini