GPT-4o mini vs Grok 4.1 Fast
GPT-4o mini vs Grok 4.1 Fast: GPT-4o mini is cheaper for input-heavy usage ($0.15/M vs $0.20/M input tokens), while Grok 4.1 Fast is better for long-context tasks (2,000,000 tokens).
Direct answer: choose GPT-4o mini for lower token spend and choose Grok 4.1 Fast 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)
GPT-4o mini
Grok 4.1 Fast
Cost Differences
Grok 4.1 Fast costs less than GPT-4o mini
Quick Recommendation
Winner for direct API pricing: GPT-4o mini. At the default workload, GPT-4o mini saves about $0.00/month ($0.00/year) versus Grok 4.1 Fast.
Feature Comparison
| Feature | GPT-4o mini | Grok 4.1 Fast |
|---|---|---|
| Provider | OpenAI | xAI |
| Input Price | $0.15/1M tokens | $0.20/1M tokens |
| Output Price | $0.60/1M tokens | $0.50/1M tokens |
| Context Window | 128,000 tokens | 2,000,000 tokens |
| Max Output | 16,384 tokens | 131,072 tokens |
| Category | efficient | efficient |
| Capabilities | textvision | textreasoningcode |
| Release Date | 7/18/2024 | 1/15/2026 |
GPT-4o mini vs Grok 4.1 Fast: Which Should You Choose?
Choosing between GPT-4o 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. Meanwhile, Grok 4.1 Fast offers a significantly larger context window at 2,000,000 tokens vs 128,000 for GPT-4o 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 $0.00/month compared to GPT-4o mini. For startups and indie developers, that difference can be significant.
Output costs matter too. GPT-4o mini charges $0.60/1M 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.
Multimodal capabilities: GPT-4o mini supports vision (image inputs) while Grok 4.1 Fast is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose GPT-4o mini when:
- • Budget is a primary concern
- • You're already using OpenAI's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose Grok 4.1 Fast when:
- • You need a larger context window (2,000,000 tokens)
- • You need more capabilities (reasoning, code)
- • 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
Pros and Caveats at a Glance
GPT-4o mini
- • Input pricing: $0.15/M tokens
- • Output pricing: $0.60/M tokens
- • Context window: 128,000 tokens
- • Max output: 16,384 tokens
Watch out for
- • Higher output cost than Grok 4.1 Fast
- • Smaller context window than Grok 4.1 Fast
Grok 4.1 Fast
- • Input pricing: $0.20/M tokens
- • Output pricing: $0.50/M tokens
- • Context window: 2,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Higher input cost than GPT-4o mini
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
GPT-4o mini (OpenAI)
Grok 4.1 Fast (xAI)
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Which is cheaper, GPT-4o mini or Grok 4.1 Fast?▼
What is the context window difference between GPT-4o mini and Grok 4.1 Fast?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare OpenAI and xAI API pricing beyond this model matchup?▼
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