Model Comparison

Grok-4 vs Grok 4.5Which is better in 2026?

Grok 4.5 significantly outperforms across most benchmarks. Grok 4.5 is 2.0x cheaper per token.

Verdict: Grok-4 vs Grok 4.5 — which is better?

Grok-4 (by xAI) and Grok 4.5 (by xAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Grok-4 outperforms in 0 benchmarks, while Grok 4.5 is better at 1 benchmark (GPQA). Grok 4.5 significantly outperforms across most benchmarks.

On price, Grok 4.5 is roughly 2.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok 4.5 also accepts a larger context window (500,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Grok-4 if…

  • you want predictable pricing at $3.00/M input and $15.00/M output

Choose Grok 4.5 if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • cost matters — it's about 2.0x cheaper per token
  • you process long inputs — it offers a 500,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Grok-4 outperforms in 0 benchmarks, while Grok 4.5 is better at 1 benchmark (GPQA).

Grok 4.5 significantly outperforms across most benchmarks.

Tue Jul 21 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Grok 4.5 costs less

For input processing, Grok-4 ($3.00/1M tokens) is 1.5x more expensive than Grok 4.5 ($2.00/1M tokens).

For output processing, Grok-4 ($15.00/1M tokens) is 2.5x more expensive than Grok 4.5 ($6.00/1M tokens).

In conclusion, Grok-4 is more expensive than Grok 4.5.*

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

Lowest available price from all providers
Tue Jul 21 2026 • llm-stats.com
xAI
Grok-4
Input tokens$3.00
Output tokens$15.00
Best providerxAI
xAI
Grok 4.5
Input tokens$2.00
Output tokens$6.00
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Grok 4.5 accepts 500,000 input tokens compared to Grok-4's 256,000 tokens. Only Grok-4 specifies output context (8,000 tokens).

xAI
Grok-4
Input256,000 tokens
Output8,000 tokens
xAI
Grok 4.5
Input500,000 tokens
Output- tokens
Tue Jul 21 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Grok-4 and Grok 4.5 support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Grok-4

Text
Images
Audio
Video

Grok 4.5

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.

Grok-4

Proprietary

Closed source

Grok 4.5

Proprietary

Closed source

Release Timeline

When each model was launched

Grok-4 was released on 2025-07-09, while Grok 4.5 was released on 2026-07-16.

Grok 4.5 is 12 months newer than Grok-4.

Grok-4

Jul 9, 2025

1.0 years ago

Grok 4.5

Jul 16, 2026

5 days ago

1.0yr newer

Knowledge Cutoff

When training data ends

Grok-4 has a knowledge cutoff of 2024-12-31, while Grok 4.5 has a cutoff of 2026-02-01.

Grok 4.5 has more recent training data (up to 2026-02-01), making it potentially better informed about events through that date compared to Grok-4 (2024-12-31).

Grok-4

Dec 2024

Grok 4.5

Feb 2026

1.2 yr newer

Provider Availability

Grok-4 is available from xAI. Grok 4.5 is available from xAI.

Grok-4

xai logo
xAI
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Grok 4.5

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

xAI

No standout differentiators in the data we have for this pair.

xAI
Larger context window (500,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher GPQA score (93.0% vs 87.5%)
xAIGrok-4
xAIGrok 4.5
Compare in Playground

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Grok-4 and Grok 4.5 side-by-side, then vote on the output you prefer.

Grok-4
✓ Preferred
Grok 4.5
Open in Playground
AI Model Comparison Table
Feature
xAI
Grok-4
xAI
Grok 4.5

FAQ

Common questions about Grok-4 vs Grok 4.5.

Which is better, Grok-4 or Grok 4.5?

Grok 4.5 significantly outperforms across most benchmarks. Grok-4 is made by xAI and Grok 4.5 is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Grok-4 compare to Grok 4.5 in benchmarks?

Grok-4 scores AIME 2025: 91.7%, HMMT25: 90.0%, GPQA: 87.5%, LiveCodeBench: 79.0%, Humanity's Last Exam: 40.0%. Grok 4.5 scores GPQA: 93.0%, Terminal-Bench 2.1: 83.3%, Artificial Analysis Coding Agent Index v1.1: 76.0%, SWE-Bench Pro: 64.7%, AA-Omniscience Index: 63.0%.

Is Grok-4 cheaper than Grok 4.5?

Grok 4.5 is 1.5x cheaper for input tokens. Grok-4 costs $3.00/M input and $15.00/M output via xai. Grok 4.5 costs $2.00/M input and $6.00/M output via xai.

What are the context window sizes for Grok-4 and Grok 4.5?

Grok-4 supports 256K tokens and Grok 4.5 supports 500K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Grok-4 and Grok 4.5?

Key differences include context window (256K vs 500K), input pricing ($3.00 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Related comparisons