Codex Mini vs Gemini 3.1 Pro
Compare OpenAI and Google AI models
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Codex Mini
Gemini 3.1 Pro
Cost Differences
Gemini 3.1 Pro costs more than Codex Mini
Feature Comparison
| Feature | Codex Mini | Gemini 3.1 Pro |
|---|---|---|
| Provider | OpenAI | |
| Input Price | $1.50/1M tokens | $2.00/1M tokens |
| Output Price | $6.00/1M tokens | $12.00/1M tokens |
| Context Window | 200,000 tokens | 1,000,000 tokens |
| Max Output | 32,768 tokens | 65,536 tokens |
| Category | efficient | flagship |
| Capabilities | textcodereasoning | textvisionaudiovideocodereasoning |
| Release Date | 2/2/2026 | 2/19/2026 |
Codex Mini vs Gemini 3.1 Pro: Which Should You Choose?
Choosing between Codex Mini and Gemini 3.1 Pro depends on your priorities: cost efficiency, context length, or raw capability. Codex Mini is the more affordable option at $1.50/1M input tokens — 25% cheaper than Gemini 3.1 Pro. Meanwhile, Gemini 3.1 Pro offers a significantly larger context window at 1,000,000 tokens vs 200,000 for Codex Mini.
These models come from different providers — OpenAI and Google — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with OpenAI, switching to Googleinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
These models target different tiers: Codex Mini is a efficient model while Gemini 3.1 Pro is flagship. This means they're optimized for different workloads. Gemini 3.1 Pro 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 $12.00 for Gemini 3.1 Pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Codex Mini has the edge here at $6.00/1M output tokens.
Multimodal capabilities: Gemini 3.1 Pro supports vision (image inputs) while Codex Mini is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose Codex Mini when:
- • Budget is a primary concern
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose Gemini 3.1 Pro when:
- • You need a larger context window (1,000,000 tokens)
- • You need more capabilities (vision, audio, video)
- • You need longer outputs (up to 65,536 tokens)
- • You're already using Google's API ecosystem
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Codex Mini (OpenAI)
Gemini 3.1 Pro (Google)
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