Model Comparison

Gemma 2 27B vs o1-previewWhich is better in 2026?

o1-preview significantly outperforms across most benchmarks.

Verdict: Gemma 2 27B vs o1-preview — which is better?

Gemma 2 27B (by Google) and o1-preview (by OpenAI) 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.

Gemma 2 27B outperforms in 0 benchmarks, while o1-preview is better at 2 benchmarks (MATH, MMLU). o1-preview significantly outperforms across most benchmarks.

Choose Gemma 2 27B if…

  • you need open weights you can self-host or fine-tune

Choose o1-preview if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • you want the most recent training data — it shipped Sep 2024

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Gemma 2 27B outperforms in 0 benchmarks, while o1-preview is better at 2 benchmarks (MATH, MMLU).

o1-preview significantly outperforms across most benchmarks.

Sun Jul 05 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only o1-preview specifies input context (128,000 tokens). Only o1-preview specifies output context (32,768 tokens).

Google
Gemma 2 27B
Input- tokens
Output- tokens
OpenAI
o1-preview
Input128,000 tokens
Output32,768 tokens
Sun Jul 05 2026 • llm-stats.com

License

Usage and distribution terms

Gemma 2 27B is licensed under Gemma, while o1-preview uses a proprietary license.

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

Gemma 2 27B

Gemma

Open weights

o1-preview

Proprietary

Closed source

Release Timeline

When each model was launched

Gemma 2 27B was released on 2024-06-27, while o1-preview was released on 2024-09-12.

o1-preview is 3 months newer than Gemma 2 27B.

Gemma 2 27B

Jun 27, 2024

2.0 years ago

o1-preview

Sep 12, 2024

1.8 years ago

2mo newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Has open weights
OpenAI
Larger context window (128,000 tokens)
Higher MATH score (85.5% vs 42.3%)
Higher MMLU score (90.8% vs 75.2%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemma 2 27B and o1-preview side-by-side, then vote on the output you prefer.

Gemma 2 27B
✓ Preferred
o1-preview
Open in Playground
AI Model Comparison Table
Feature
Google
Gemma 2 27B
OpenAI
o1-preview

FAQ

Common questions about Gemma 2 27B vs o1-preview.

Which is better, Gemma 2 27B or o1-preview?

o1-preview significantly outperforms across most benchmarks. Gemma 2 27B is made by Google and o1-preview is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemma 2 27B compare to o1-preview in benchmarks?

Gemma 2 27B scores ARC-E: 88.6%, HellaSwag: 86.4%, BoolQ: 84.8%, TriviaQA: 83.7%, Winogrande: 83.7%. o1-preview scores MGSM: 90.8%, MMLU: 90.8%, MATH: 85.5%, GPQA: 73.3%, LiveBench: 52.3%.

What are the context window sizes for Gemma 2 27B and o1-preview?

Gemma 2 27B supports an unknown number of tokens and o1-preview supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemma 2 27B and o1-preview?

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

Who makes Gemma 2 27B and o1-preview?

Gemma 2 27B is developed by Google and o1-preview is developed by OpenAI.

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