GPT-6 Rosalind vs Grok 4 Fast
Comparing GPT-6 Rosalind and Grok 4 Fast across benchmarks, pricing, and capabilities.
OpenAI · xAI · Updated for 2026
Which is better?
GPT-6 Rosalind and Grok 4 Fast trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.
On price, Grok 4 Fast is roughly 109.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-6 Rosalind
- you want the most recent training data — it shipped Oct 2026
Choose Grok 4 Fast
- cost matters — it's about 109.1x cheaper per token
At a glance
The differences that matter most.
Individual benchmarks
0 reported for GPT-6 Rosalind · 7 for Grok 4 Fast
GPT-6 Rosalind and Grok 4 Fastdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-6 Rosalind ($15.00/1M tokens) is 75.0x more expensive than Grok 4 Fast ($0.20/1M tokens).
For output processing, GPT-6 Rosalind ($75.00/1M tokens) is 150.0x more expensive than Grok 4 Fast ($0.50/1M tokens).
In conclusion, GPT-6 Rosalind is more expensive than Grok 4 Fast.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Only Grok 4 Fast specifies input context (2,000,000 tokens). Only Grok 4 Fast specifies output context (30,000 tokens).
Input capabilities
Documented input modalities across available providers
Both GPT-6 Rosalind and Grok 4 Fast support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-6 Rosalind
Grok 4 Fast
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
GPT-6 Rosalind was released on 2026-10-30, while Grok 4 Fast was released on 2025-08-28.
GPT-6 Rosalind is 14 months newer than Grok 4 Fast.
Oct 30, 2026
5 days ago
1.2yr newerAug 28, 2025
1.2 years ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GPT-6 Rosalind is available from OpenAI. Grok 4 Fast is available from xAI.
GPT-6 Rosalind
Grok 4 Fast
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-6 Rosalind and Grok 4 Fast side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-6 Rosalind vs Grok 4 Fast.