Grok 4.1 Fast is $4.8 cheaper per 1M input tokens (96% lower; 25x difference).
API cost decision in 10 seconds
🔥Grok 4.1 Fast vs 🔥GPT-5.5
Pick Grok 4.1 Fast when budget and context both matter.
Pricing data updated:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Grok 4.1 Fast when budget and context both matter.
On the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $20 for GPT-5.5, saving $19.55 (97.8% lower).
Cost-first pickGrok 4.1 Fast
Context-first pickGrok 4.1 Fast
Sample savings$19.5597.8%
10x traffic gap$195.5
Grok 4.1 Fast is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $195.5. Use the calculator below to replace the sample workload with your own token volume.
Grok 4.1 Fast is $29.5 cheaper per 1M output tokens (98.3% lower; 60x difference).
Grok 4.1 Fast has 950K more context (1.9x larger).
Grok 4.1 Fast is $19.55 cheaper on the standard workload (97.8% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Grok 4.1 Fast has the lower input price; Grok 4.1 Fast has the lower output price; Grok 4.1 Fast offers the larger context window. For the 1M input plus 500K output sample, Grok 4.1 Fast is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.45 for Grok 4.1 Fast and $20 for GPT-5.5.
Choose Grok 4.1 Fast when you care most about lower input-token price, lower output-token price, and larger context window.
Choose GPT-5.5 when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
- On the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $20 for GPT-5.5, saving $19.55 (97.8% lower).
- Grok 4.1 Fast is $19.55 cheaper on the standard workload (97.8% lower).
- Grok 4.1 Fast is $4.8 cheaper per 1M input tokens (96% lower; 25x difference).
- Grok 4.1 Fast is $29.5 cheaper per 1M output tokens (98.3% lower; 60x difference).
- Grok 4.1 Fast has 950K more context (1.9x larger).
| Feature | 🔥Grok 4.1 Fast (xAI) | 🔥GPT-5.5 (OpenAI) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.2 | $5 |
| Completion Price per 1M tokens | $0.5 | $30 |
| Sample Workload Cost 1M input + 500K output | $0.45 | $20 |
| Context Window | 2M | 1.05M |
| Release Date | 2025-11-19 | 2026-04-24 |
| Popularity Rank current rank | #18 | #19 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Grok 4.1 Fast | On the standard 1M input plus 500K output workload, Grok 4.1 Fast is estimated at $0.45 vs $20 for GPT-5.5, saving $19.55 (97.8% lower). |
| High-volume input processing | Grok 4.1 Fast | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Grok 4.1 Fast | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Grok 4.1 Fast | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
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