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GPT-6 Astra vs Grok 4.3

GPT-6 Astra leads the LLM Stats Score 59.6 to 22.3. Grok 4.3 is 12.8x cheaper per token.

OpenAI · xAI · Updated for 2026

Which is better?

GPT-6 Astra leads the overall LLM Stats Score 59.6 to 22.3, ranking #1 overall.

On price, Grok 4.3 is roughly 12.8x 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 59.6 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and agents — it leads those capability indexes
  • 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 4.3

  • cost matters — it's about 12.8x cheaper per token

At a glance

The differences that matter most.

GPT-6 Astra
OpenAI
Grok 4.3
xAI
Core performance indexes
LLM Stats Score
59.6
#1
22.3
#177
Reasoning
57.5
#1
22.6
#169
Agents
45.7
#1
10.5
#115
Cost, coverage & limits
Benchmark wins
—
—
Input price
$10.00 / M
$1.25 / M
Output price
$50.00 / M
$2.50 / M
Context window
1,050,000
1,000,000

Individual benchmarks

22 reported for GPT-6 Astra · 1 for Grok 4.3

No common benchmarks found

GPT-6 Astra and Grok 4.3don'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

Grok 4.3 costs less

For input processing, GPT-6 Astra ($10.00/1M tokens) is 8.0x more expensive than Grok 4.3 ($1.25/1M tokens).

For output processing, GPT-6 Astra ($50.00/1M tokens) is 20.0x more expensive than Grok 4.3 ($2.50/1M tokens).

In conclusion, GPT-6 Astra is more expensive than Grok 4.3.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Mon Sep 21 2026 • llm-stats.com
OpenAI
GPT-6 Astra
Input tokens$10.00
Output tokens$50.00
Best providerOpenAI
xAI
Grok 4.3
Input tokens$1.25
Output tokens$2.50
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-6 Astra accepts 1,050,000 input tokens compared to Grok 4.3's 1,000,000 tokens. Only GPT-6 Astra specifies output context (128,000 tokens).

OpenAI
GPT-6 Astra
Input1,050,000 tokens
Output128,000 tokens
xAI
Grok 4.3
Input1,000,000 tokens
Output- tokens
Mon Sep 21 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

GPT-6 Astra supports multimodal inputs, whereas Grok 4.3 does not.

GPT-6 Astra can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-6 Astra

Text
Images
Audio
Video

Grok 4.3

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-6 Astra

Proprietary

Closed source

Grok 4.3

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-6 Astra was released on 2026-09-04, while Grok 4.3 was released on 2026-05-06.

GPT-6 Astra is 4 months newer than Grok 4.3.

GPT-6 Astra

Sep 4, 2026

2 weeks ago

4mo newer
Grok 4.3

May 6, 2026

4 months ago

Knowledge Cutoff

When training data ends

GPT-6 Astra has a documented knowledge cutoff of 2026-04-30, while Grok 4.3's cutoff date is not specified.

We can confirm GPT-6 Astra's training data extends to 2026-04-30, but cannot make a direct comparison without Grok 4.3's cutoff date.

GPT-6 Astra

Apr 2026

Grok 4.3

—

Provider Availability

GPT-6 Astra is available from OpenAI. Grok 4.3 is available from xAI.

GPT-6 Astra

openai logo
OpenAI
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Grok 4.3

xai logo
xAI
Input Price:Input: $1.25/1MOutput Price:Output: $2.50/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against GPT-6 Astra and Grok 4.3 side-by-side, then vote on the output you prefer.

GPT-6 Astra
✓ Preferred
Grok 4.3
Open in Playground

FAQ

Common questions about GPT-6 Astra vs Grok 4.3.

Which is better, GPT-6 Astra or Grok 4.3?

GPT-6 Astra leads the LLM Stats Score 59.6 to 22.3. GPT-6 Astra is made by OpenAI and Grok 4.3 is made by xAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6 Astra compare to Grok 4.3 in benchmarks?

GPT-6 Astra scores ExploitBench: 100.0%, ARC-AGI-3: 99.9%, ARC-AGI: 98.5%, FrontierMath Tier 4 (v2): 97.6%, GPQA: 96.0%. Grok 4.3 scores Finance Agent v2: 37.7%.

Is GPT-6 Astra cheaper than Grok 4.3?

Grok 4.3 is 8.0x cheaper for input tokens. GPT-6 Astra costs $10.00/M input and $50.00/M output via openai. Grok 4.3 costs $1.25/M input and $2.50/M output via xai.

What are the context window sizes for GPT-6 Astra and Grok 4.3?

GPT-6 Astra supports 1.1M tokens and Grok 4.3 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6 Astra and Grok 4.3?

Key differences include LLM Stats Score (59.6 vs 22.3), context window (1.1M vs 1.0M), input pricing ($10.00 vs $1.25/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Astra and Grok 4.3?

GPT-6 Astra is developed by OpenAI and Grok 4.3 is developed by xAI.

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