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GPT-5 vs Grok Code Fast 1

GPT-5 significantly outperforms across most benchmarks. Grok Code Fast 1 is 6.5x cheaper per token.

OpenAI · xAI · Updated for 2026

Which is better?

GPT-5 outperforms in 1 benchmarks (SWE-Bench Verified), while Grok Code Fast 1 is better at 0 benchmarks. GPT-5 significantly outperforms across most benchmarks.

On price, Grok Code Fast 1 is roughly 6.5x 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.

Based on current benchmark, pricing, and model metadata for 2026.

Choose GPT-5

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 400,000 token context window

Choose Grok Code Fast 1

  • cost matters — it's about 6.5x cheaper per token
  • you want the most recent training data — it shipped Aug 2025

At a glance

The differences that matter most.

GPT-5
OpenAI
Grok Code Fast 1
xAI
Benchmark wins
1 of 1
0 of 1
Input price
$1.25 / M
$0.20 / M
Output price
$10.00 / M
$1.50 / M
Context window
400,000
256,000
Released
Aug 2025
Aug 2025
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

GPT-5 outperforms in 1 benchmarks (SWE-Bench Verified), while Grok Code Fast 1 is better at 0 benchmarks.

GPT-5 significantly outperforms across most benchmarks.

Tue Aug 25 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Grok Code Fast 1 costs less

For input processing, GPT-5 ($1.25/1M tokens) is 6.3x more expensive than Grok Code Fast 1 ($0.20/1M tokens).

For output processing, GPT-5 ($10.00/1M tokens) is 6.7x more expensive than Grok Code Fast 1 ($1.50/1M tokens).

In conclusion, GPT-5 is more expensive than Grok Code Fast 1.*

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

Lowest available price from all providers
Tue Aug 25 2026 • llm-stats.com
OpenAI
GPT-5
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
xAI
Grok Code Fast 1
Input tokens$0.20
Output tokens$1.50
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 Code Fast 1's 256,000 tokens. GPT-5 can generate longer responses up to 128,000 tokens, while Grok Code Fast 1 is limited to 10,000 tokens.

OpenAI
GPT-5
Input400,000 tokens
Output128,000 tokens
xAI
Grok Code Fast 1
Input256,000 tokens
Output10,000 tokens
Tue Aug 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5 supports multimodal inputs, whereas Grok Code Fast 1 does not.

GPT-5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT-5

Text
Images
Audio
Video

Grok Code Fast 1

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 Code Fast 1

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 was released on 2025-08-07, while Grok Code Fast 1 was released on 2025-08-28.

Grok Code Fast 1 is 1 month newer than GPT-5.

GPT-5

Aug 7, 2025

1.0 years ago

Grok Code Fast 1

Aug 28, 2025

12 months ago

3w newer

Knowledge Cutoff

When training data ends

GPT-5 has a documented knowledge cutoff of 2024-09-30, while Grok Code Fast 1's cutoff date is not specified.

We can confirm GPT-5's training data extends to 2024-09-30, but cannot make a direct comparison without Grok Code Fast 1's cutoff date.

GPT-5

Sep 2024

Grok Code Fast 1

—

Provider Availability

GPT-5 is available from OpenAI. Grok Code Fast 1 is available from xAI.

GPT-5

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

Grok Code Fast 1

xai logo
xAI
Input Price:Input: $0.20/1MOutput Price:Output: $1.50/1M
* 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-5 and Grok Code Fast 1 side-by-side, then vote on the output you prefer.

GPT-5
✓ Preferred
Grok Code Fast 1
Open in Playground

FAQ

Common questions about GPT-5 vs Grok Code Fast 1.

Which is better, GPT-5 or Grok Code Fast 1?

GPT-5 significantly outperforms across most benchmarks. GPT-5 is made by OpenAI and Grok Code Fast 1 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 Code Fast 1 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 Code Fast 1 scores SWE-Bench Verified: 70.8%.

Is GPT-5 cheaper than Grok Code Fast 1?

Grok Code Fast 1 is 6.3x cheaper for input tokens. GPT-5 costs $1.25/M input and $10.00/M output via openai. Grok Code Fast 1 costs $0.20/M input and $1.50/M output via xai.

What are the context window sizes for GPT-5 and Grok Code Fast 1?

GPT-5 supports 400K tokens and Grok Code Fast 1 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 Code Fast 1?

Key differences include context window (400K vs 256K), input pricing ($1.25 vs $0.20/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 and Grok Code Fast 1?

GPT-5 is developed by OpenAI and Grok Code Fast 1 is developed by xAI.

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