+
+
+
+
+
+
+
+
VS
VS
VS
VS
VS
VS
Grok 4 Fast vs Llama 3.1 405B Instruct
Comprehensive side-by-side LLM comparison
Grok 4 Fast leads with 35.0% higher average benchmark score. Grok 4 Fast offers 1.8M more tokens in context window than Llama 3.1 405B Instruct. Grok 4 Fast is $1.08 cheaper per million tokens. Grok 4 Fast supports multimodal inputs. Llama 3.1 405B Instruct is available on 8 providers. Overall, Grok 4 Fast is the stronger choice for coding tasks.
+
+
+
+
xAI
Grok 4 Fast is a multimodal language model developed by xAI. It achieves strong performance with an average score of 73.0% across 7 benchmarks. It excels particularly in SimpleQA (95.0%), HMMT 2025 (93.3%), AIME 2025 (92.0%). With a 2.0M token context window, it can handle extensive documents and complex multi-turn conversations. The model is available through 1 API provider. As a multimodal model, it can process and understand text, images, and other input formats seamlessly. Released in 2025, it represents xAI's latest advancement in AI technology.
+
+
+
+
Meta
Llama 3.1 405B was developed as Meta's largest open-source language model, designed to provide frontier-level capabilities with 405 billion parameters. Built to demonstrate that open-source models can match proprietary systems in capability, it enables researchers and developers to experiment with and deploy a powerful foundation model without licensing restrictions.
1 year newer
Llama 3.1 405B Instruct
Meta
2024-07-23
Grok 4 Fast
xAI
2025-08-28
+
+
+
+
+
+
+
+
+
+
+
+
Pricing Comparison
Cost per million tokens (USD)
+
+
+
+
Grok 4 Fast
Input:$0.20
Output:$0.50($1.08 cheaper)
+
+
+
+
Llama 3.1 405B Instruct
Input:$0.89
Output:$0.89
Performance Metrics
Context window and performance specifications
Average performance across 1 common benchmarks
+
+
+
+
Grok 4 Fast
Average Score:85.7%(+35.0%)
+
+
+
+
Llama 3.1 405B Instruct
Average Score:50.7%
Provider Availability & Performance
Available providers and their performance metrics
+
+
+
+
Grok 4 Fast
1 providers
xAI
Throughput: 90 tok/s
+
+
+
+
Llama 3.1 405B Instruct
8 providers
+
+
+
+
Grok 4 Fast
Avg Score:85.7%(+35.0%)
Providers:1
+
+
+
+
Llama 3.1 405B Instruct
Avg Score:50.7%
Providers:8