Reasoning power without the price tag

OpenAI's o3-mini is the "thinking" model that makes reasoning accessible. While o1 costs $15/M input tokens, o3-mini delivers comparable or better performance at $1.10/M — a 93% cost reduction. It uses chain-of-thought reasoning to solve complex math, coding, and science problems that trip up standard models.

The key insight: o3-mini doesn't just give you an answer — it shows its work. You can see the reasoning chain, which makes it easier to catch errors and build trust. For developers, this means better debugging suggestions. For students, it means a tutor that explains, not just answers.

Who it's for: Developers solving complex bugs, students doing STEM homework, researchers doing analysis, and anyone who needs "thinking" AI without paying o1 prices.

Key features

Think Chain-of-thought reasoning

Thinks through problems step by step before answering. See the reasoning chain, catch errors, build trust. 93% cheaper than o1 with comparable performance.

STEM Math and science excellence

Beats o1 on AIME 2024 (math olympiad), GPQA (graduate-level science), and Codeforces competitive programming. The best affordable reasoning model.

Speed 3 reasoning effort levels

Choose low, medium, or high reasoning effort. Low is fast and cheap for simple tasks. High is slower but excels on hard problems. You control the cost/quality tradeoff.

Free Available in ChatGPT free tier

Free users get limited o3-mini queries per day. Plus users ($20/mo) get higher limits. API pricing is $1.10/M input, $4.40/M output tokens.

The honest take

✓ What works

93% cheaper than o1 with comparable or better reasoning
Free tier in ChatGPT — no cost to try
Transparent reasoning chain — see how it thinks
3 effort levels let you control speed vs quality
Dominates STEM benchmarks (math, science, coding)

✗ What doesn't

Slower than standard models — reasoning takes time
Can over-think simple questions (use low effort for those)
Not great for creative writing or open-ended tasks
Free tier has strict daily limits

Verdict

o3-mini is the reasoning model for everyone. At $1.10/M tokens (vs o1's $15/M), it makes chain-of-thought thinking accessible for everyday use. If you do any math, coding, or analysis work, o3-mini should be in your toolkit. Use it for hard problems, use standard GPT-4o for everything else.

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