GPT-4o vs Grok-4 Heavy
Grok-4 Heavy significantly outperforms across most benchmarks.
OpenAI · xAI · Updated for 2026
Which is better?
GPT-4o outperforms in 0 benchmarks, while Grok-4 Heavy is better at 1 benchmark (GPQA). Grok-4 Heavy significantly outperforms across most benchmarks.
Based on current benchmark, pricing, and model metadata for 2026.
Choose GPT-4o
- you want predictable pricing at $2.50/M input and $10.00/M output
Choose Grok-4 Heavy
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
GPT-4o outperforms in 0 benchmarks, while Grok-4 Heavy is better at 1 benchmark (GPQA).
Grok-4 Heavy significantly outperforms across most benchmarks.
Arena Performance
Playground indexes and blind preference scores
Context Window
Maximum input and output token capacity
Only GPT-4o specifies input context (128,000 tokens). Only GPT-4o specifies output context (4,096 tokens).
Input Capabilities
Supported data types and modalities
Both GPT-4o and Grok-4 Heavy support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-4o
Grok-4 Heavy
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-4o was released on 2024-05-13, while Grok-4 Heavy's release date is not specified.
We can confirm GPT-4o's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.
May 13, 2024
2.3 years ago
—
Knowledge Cutoff
When training data ends
Grok-4 Heavy has a documented knowledge cutoff of 2024-12-31, while GPT-4o's cutoff date is not specified.
We can confirm Grok-4 Heavy's training data extends to 2024-12-31, but cannot make a direct comparison without GPT-4o's cutoff date.
—
Dec 2024
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-4o and Grok-4 Heavy side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-4o vs Grok-4 Heavy.