Codex Mini vs o3-mini
Codex Mini vs o3-mini: o3-mini is cheaper for input-heavy usage ($1.10/M vs $1.50/M input tokens), while o3-mini is better for long-context tasks (500,000 tokens).
Direct answer: choose o3-mini for lower token spend and choose o3-mini when your workload needs longer context.
Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Codex Mini
o3-mini
Cost Differences
o3-mini costs less than Codex Mini
Quick Recommendation
Winner for direct API pricing: o3-mini. At the default workload, o3-mini saves about $3.60/month ($43.80/year) versus Codex Mini.
Feature Comparison
| Feature | Codex Mini | o3-mini |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Input Price | $1.50/1M tokens | $1.10/1M tokens |
| Output Price | $6.00/1M tokens | $4.40/1M tokens |
| Context Window | 200,000 tokens | 500,000 tokens |
| Max Output | 32,768 tokens | 65,536 tokens |
| Category | efficient | reasoning |
| Capabilities | textcodereasoning | textreasoningcode |
| Release Date | 2/2/2026 | 1/31/2025 |
Codex Mini vs o3-mini: Which Should You Choose?
Choosing between Codex Mini and o3-mini depends on your priorities: cost efficiency, context length, or raw capability. o3-mini is the more affordable option at $1.10/1M input tokens — 27% cheaper than Codex Mini. Meanwhile, o3-mini offers a significantly larger context window at 500,000 tokens vs 200,000 for Codex Mini.
These models target different tiers: Codex Mini is a efficient model while o3-mini is reasoning. This means they're optimized for different workloads. o3-mini targets more demanding workloads, while Codex Mini provides a cost-effective option for everyday tasks.
Output costs matter too. Codex Mini charges $6.00/1M output tokens vs $4.40 for o3-mini. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. o3-mini has the edge here at $4.40/1M output tokens.
Best Use Cases
Choose Codex Mini when:
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose o3-mini when:
- • Budget is a primary concern
- • You need a larger context window (500,000 tokens)
- • You need longer outputs (up to 65,536 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Codex Mini
- • Input pricing: $1.50/M tokens
- • Output pricing: $6.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 32,768 tokens
Watch out for
- • Higher input cost than o3-mini
- • Higher output cost than o3-mini
- • Smaller context window than o3-mini
o3-mini
- • Input pricing: $1.10/M tokens
- • Output pricing: $4.40/M tokens
- • Context window: 500,000 tokens
- • Max output: 65,536 tokens
Watch out for
- • Trade-offs are minor in this matchup.
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Codex Mini (OpenAI)
o3-mini (OpenAI)
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