Model Comparison

GPT-5 vs Grok-4Which is better in 2026?

Grok-4 shows notably better performance in the majority of benchmarks. GPT-5 is 1.7x cheaper per token.

Verdict: GPT-5 vs Grok-4 — which is better?

GPT-5 (by OpenAI) and Grok-4 (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.

GPT-5 outperforms in 1 benchmarks (AIME 2025), while Grok-4 is better at 2 benchmarks (GPQA, Humanity's Last Exam). Grok-4 shows notably better performance in the majority of benchmarks.

On price, GPT-5 is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5 also accepts a larger context window (400,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-5 if…

  • cost matters — it's about 1.7x cheaper per token
  • you process long inputs — it offers a 400,000 token context window
  • you want the most recent training data — it shipped Aug 2025

Choose Grok-4 if…

  • you want the strongest raw capability — it leads on 2 of 3 shared benchmarks
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Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

GPT-5 outperforms in 1 benchmarks (AIME 2025), while Grok-4 is better at 2 benchmarks (GPQA, Humanity's Last Exam).

Grok-4 shows notably better performance in the majority of benchmarks.

Sat Jun 20 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5 costs less

For input processing, GPT-5 ($1.25/1M tokens) is 2.4x cheaper than Grok-4 ($3.00/1M tokens).

For output processing, GPT-5 ($10.00/1M tokens) is 1.5x cheaper than Grok-4 ($15.00/1M tokens).

In conclusion, Grok-4 is more expensive than GPT-5.*

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

Lowest available price from all providers
Sat Jun 20 2026 • llm-stats.com
OpenAI
GPT-5
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
xAI
Grok-4
Input tokens$3.00
Output tokens$15.00
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5 accepts 400,000 input tokens compared to Grok-4's 256,000 tokens. GPT-5 can generate longer responses up to 128,000 tokens, while Grok-4 is limited to 8,000 tokens.

OpenAI
GPT-5
Input400,000 tokens
Output128,000 tokens
xAI
Grok-4
Input256,000 tokens
Output8,000 tokens
Sat Jun 20 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5 and Grok-4 support multimodal inputs.

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

GPT-5

Text
Images
Audio
Video

Grok-4

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-5

Proprietary

Closed source

Grok-4

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 was released on 2025-08-07, while Grok-4 was released on 2025-07-09.

GPT-5 is 1 month newer than Grok-4.

GPT-5

Aug 7, 2025

10 months ago

4w newer
Grok-4

Jul 9, 2025

11 months ago

Knowledge Cutoff

When training data ends

GPT-5 has a knowledge cutoff of 2024-09-30, while Grok-4 has a cutoff of 2024-12-31.

Grok-4 has more recent training data (up to 2024-12-31), making it potentially better informed about events through that date compared to GPT-5 (2024-09-30).

GPT-5

Sep 2024

Grok-4

Dec 2024

3 mo newer

Provider Availability

GPT-5 is available from OpenAI. Grok-4 is available from xAI.

GPT-5

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M

Grok-4

xai logo
xAI
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

OpenAI
Larger context window (400,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher AIME 2025 score (94.6% vs 91.7%)
xAI
Higher GPQA score (87.5% vs 85.7%)
Higher Humanity's Last Exam score (40.0% vs 24.8%)
OpenAIGPT-5
xAIGrok-4
Compare in Playground

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-5
xAI
Grok-4

FAQ

Common questions about GPT-5 vs Grok-4.

Which is better, GPT-5 or Grok-4?

Grok-4 shows notably better performance in the majority of benchmarks. GPT-5 is made by OpenAI and Grok-4 is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5 compare to Grok-4 in benchmarks?

GPT-5 scores SWE-Lancer (IC-Diamond subset): 100.0%, COLLIE: 99.0%, Tau2 Telecom: 96.7%, OpenAI-MRCR: 2 needle 128k: 95.2%, AIME 2025: 94.6%. Grok-4 scores AIME 2025: 91.7%, HMMT25: 90.0%, GPQA: 87.5%, LiveCodeBench: 79.0%, Humanity's Last Exam: 40.0%.

Is GPT-5 cheaper than Grok-4?

GPT-5 is 2.4x cheaper for input tokens. GPT-5 costs $1.25/M input and $10.00/M output via openai. Grok-4 costs $3.00/M input and $15.00/M output via xai.

What are the context window sizes for GPT-5 and Grok-4?

GPT-5 supports 400K tokens and Grok-4 supports 256K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5 and Grok-4?

Key differences include context window (400K vs 256K), input pricing ($1.25 vs $3.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 and Grok-4?

GPT-5 is developed by OpenAI and Grok-4 is developed by xAI.

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