Model Comparison

GPT-5.4 vs DiffusionGemma 26B-A4BWhich is better in 2026?

GPT-5.4 significantly outperforms across most benchmarks.

Verdict: GPT-5.4 vs DiffusionGemma 26B-A4B — which is better?

GPT-5.4 (by OpenAI) and DiffusionGemma 26B-A4B (by Google) 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-5.4 outperforms in 4 benchmarks (GPQA, Humanity's Last Exam, MMMU-Pro, OmniDocBench 1.5), while DiffusionGemma 26B-A4B is better at 0 benchmarks. GPT-5.4 significantly outperforms across most benchmarks.

Choose GPT-5.4 if…

  • you want the strongest raw capability — it leads on 4 of 4 shared benchmarks

Choose DiffusionGemma 26B-A4B if…

  • you want the most recent training data — it shipped Jun 2026
  • you need open weights you can self-host or fine-tune
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

GPT-5.4 outperforms in 4 benchmarks (GPQA, Humanity's Last Exam, MMMU-Pro, OmniDocBench 1.5), while DiffusionGemma 26B-A4B is better at 0 benchmarks.

GPT-5.4 significantly outperforms across most benchmarks.

Wed Jun 10 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only GPT-5.4 specifies input context (1,000,000 tokens). Only GPT-5.4 specifies output context (128,000 tokens).

OpenAI
GPT-5.4
Input1,000,000 tokens
Output128,000 tokens
Google
DiffusionGemma 26B-A4B
Input- tokens
Output- tokens
Wed Jun 10 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.4 and DiffusionGemma 26B-A4B support multimodal inputs.

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

GPT-5.4

Text
Images
Audio
Video

DiffusionGemma 26B-A4B

Text
Images
Audio
Video

License

Usage and distribution terms

GPT-5.4 is licensed under a proprietary license, while DiffusionGemma 26B-A4B uses Apache 2.0.

License differences may affect how you can use these models in commercial or open-source projects.

GPT-5.4

Proprietary

Closed source

DiffusionGemma 26B-A4B

Apache 2.0

Open weights

Release Timeline

When each model was launched

GPT-5.4 was released on 2026-03-05, while DiffusionGemma 26B-A4B was released on 2026-06-10.

DiffusionGemma 26B-A4B is 3 months newer than GPT-5.4.

GPT-5.4

Mar 5, 2026

3 months ago

DiffusionGemma 26B-A4B

Jun 10, 2026

0 days ago

3mo newer

Knowledge Cutoff

When training data ends

DiffusionGemma 26B-A4B has a documented knowledge cutoff of 2025-01-01, while GPT-5.4's cutoff date is not specified.

We can confirm DiffusionGemma 26B-A4B's training data extends to 2025-01-01, but cannot make a direct comparison without GPT-5.4's cutoff date.

GPT-5.4

—

DiffusionGemma 26B-A4B

Jan 2025

Outputs Comparison

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Key Takeaways

OpenAI
Larger context window (1,000,000 tokens)
Higher GPQA score (92.8% vs 73.2%)
Higher Humanity's Last Exam score (39.8% vs 11.9%)
Higher MMMU-Pro score (81.2% vs 54.3%)
Higher OmniDocBench 1.5 score (89.1% vs 31.9%)
Google
Has open weights

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-5.4
Google
DiffusionGemma 26B-A4B

FAQ

Common questions about GPT-5.4 vs DiffusionGemma 26B-A4B.

Which is better, GPT-5.4 or DiffusionGemma 26B-A4B?

GPT-5.4 significantly outperforms across most benchmarks. GPT-5.4 is made by OpenAI and DiffusionGemma 26B-A4B is made by Google. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5.4 compare to DiffusionGemma 26B-A4B in benchmarks?

GPT-5.4 scores Tau2 Telecom: 98.9%, ARC-AGI: 93.7%, Graphwalks BFS <128k: 93.0%, GPQA: 92.8%, Graphwalks parents <128k: 89.8%. DiffusionGemma 26B-A4B scores MMMLU: 81.5%, MMLU-Pro: 77.6%, GPQA: 73.2%, MathVision: 70.5%, AIME 2026: 69.1%.

What are the context window sizes for GPT-5.4 and DiffusionGemma 26B-A4B?

GPT-5.4 supports 1.0M tokens and DiffusionGemma 26B-A4B supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5.4 and DiffusionGemma 26B-A4B?

Key differences include licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.4 and DiffusionGemma 26B-A4B?

GPT-5.4 is developed by OpenAI and DiffusionGemma 26B-A4B is developed by Google.

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