Codex Mini vs Grok 4.1 Fast
Compare OpenAI and xAI AI models
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Codex Mini
Grok 4.1 Fast
Cost Differences
Grok 4.1 Fast costs less than Codex Mini
Feature Comparison
| Feature | Codex Mini | Grok 4.1 Fast |
|---|---|---|
| Provider | OpenAI | xAI |
| Input Price | $1.50/1M tokens | $0.20/1M tokens |
| Output Price | $6.00/1M tokens | $0.50/1M tokens |
| Context Window | 200,000 tokens | 2,000,000 tokens |
| Max Output | 32,768 tokens | 131,072 tokens |
| Category | efficient | efficient |
| Capabilities | textcodereasoning | textreasoningcode |
| Release Date | 2/2/2026 | 1/15/2026 |
Codex Mini vs Grok 4.1 Fast: Which Should You Choose?
Choosing between Codex Mini and Grok 4.1 Fast depends on your priorities: cost efficiency, context length, or raw capability. Grok 4.1 Fast is the more affordable option at $0.20/1M input tokens — 87% cheaper than Codex Mini. Meanwhile, Grok 4.1 Fast offers a significantly larger context window at 2,000,000 tokens vs 200,000 for Codex Mini.
These models come from different providers — OpenAI and xAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with OpenAI, switching to xAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
Both models are in the efficient category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: Grok 4.1 Fast would save you roughly $1,215.00/month compared to Codex Mini. For startups and indie developers, that difference can be significant.
Output costs matter too. Codex Mini charges $6.00/1M output tokens vs $0.50 for Grok 4.1 Fast. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Grok 4.1 Fast has the edge here at $0.50/1M 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 Grok 4.1 Fast when:
- • Budget is a primary concern
- • You need a larger context window (2,000,000 tokens)
- • You need longer outputs (up to 131,072 tokens)
- • You're already using xAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Codex Mini (OpenAI)
Grok 4.1 Fast (xAI)
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