GPT-6 Astra vs Grok 4.5
GPT-6 Astra leads the LLM Stats Score 60.7 to 45.5. Grok 4.5 is 6.7x cheaper per token.
OpenAI · xAI · Updated for 2026
Which is better?
GPT-6 Astra leads the overall LLM Stats Score 60.7 to 45.5, ranking #1 overall.
In the 4 individual benchmarks reported for both models, GPT-6 Astra wins 4; this is a narrower head-to-head signal than the composite indexes.
On price, Grok 4.5 is roughly 6.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-6 Astra also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-6 Astra
- overall performance matters — it scores 60.7 and ranks #1 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 4 of 4 exact shared results
- you process long inputs — it offers a 1,050,000 token context window
- you want the most recent training data — it shipped Sep 2026
Choose Grok 4.5
- cost matters — it's about 6.7x cheaper per token
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
22 reported for GPT-6 Astra · 15 for Grok 4.5
GPT-6 Astra outperforms in 4 benchmarks (DeepSWE 1.1, FrontierCode 1.1, GPQA, Terminal-Bench 4.0), while Grok 4.5 is better at 0 benchmarks.
GPT-6 Astra significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, GPT-6 Astra ($10.00/1M tokens) is 5.0x more expensive than Grok 4.5 ($2.00/1M tokens).
For output processing, GPT-6 Astra ($50.00/1M tokens) is 8.3x more expensive than Grok 4.5 ($6.00/1M tokens).
In conclusion, GPT-6 Astra is more expensive than Grok 4.5.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-6 Astra accepts 1,050,000 input tokens compared to Grok 4.5's 500,000 tokens. Only GPT-6 Astra specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
Both GPT-6 Astra and Grok 4.5 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
GPT-6 Astra
Grok 4.5
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 Astra was released on 2026-09-04, while Grok 4.5 was released on 2026-07-16.
GPT-6 Astra is 2 months newer than Grok 4.5.
Sep 4, 2026
1 days ago
1mo newerJul 16, 2026
1 months ago
Knowledge Cutoff
When training data ends
GPT-6 Astra has a knowledge cutoff of 2026-04-30, while Grok 4.5 has a cutoff of 2026-02-01.
GPT-6 Astra has more recent training data (up to 2026-04-30), making it potentially better informed about events through that date compared to Grok 4.5 (2026-02-01).
Apr 2026
2 mo newerFeb 2026
Provider Availability
GPT-6 Astra is available from OpenAI. Grok 4.5 is available from xAI.
GPT-6 Astra
Grok 4.5
Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-6 Astra and Grok 4.5 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-6 Astra vs Grok 4.5.