Model Comparison

Gemma 2 9B vs GPT OSS 20BWhich is better in 2026?

GPT OSS 20B significantly outperforms across most benchmarks.

Verdict: Gemma 2 9B vs GPT OSS 20B — which is better?

Gemma 2 9B (by Google) and GPT OSS 20B (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 9B outperforms in 0 benchmarks, while GPT OSS 20B is better at 1 benchmark (MMLU). GPT OSS 20B significantly outperforms across most benchmarks.

Choose Gemma 2 9B if…

  • you are already invested in the Google ecosystem

Choose GPT OSS 20B if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you want the most recent training data — it shipped Aug 2025
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Gemma 2 9B outperforms in 0 benchmarks, while GPT OSS 20B is better at 1 benchmark (MMLU).

GPT OSS 20B significantly outperforms across most benchmarks.

Thu Jun 25 2026 • llm-stats.com

Arena Performance

Human preference votes

Model Size

Parameter count comparison

11.7B diff

GPT OSS 20B has 11.7B more parameters than Gemma 2 9B, making it 126.2% larger.

Google
Gemma 2 9B
9.2Bparameters
OpenAI
GPT OSS 20B
20.9Bparameters
9.2B
Gemma 2 9B
20.9B
GPT OSS 20B

Context Window

Maximum input and output token capacity

Only GPT OSS 20B specifies input context (131,072 tokens). Only GPT OSS 20B specifies output context (32,768 tokens).

Google
Gemma 2 9B
Input- tokens
Output- tokens
OpenAI
GPT OSS 20B
Input131,072 tokens
Output32,768 tokens
Thu Jun 25 2026 • llm-stats.com

License

Usage and distribution terms

Gemma 2 9B is licensed under Gemma, while GPT OSS 20B uses Apache 2.0.

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

Gemma 2 9B

Gemma

Open weights

GPT OSS 20B

Apache 2.0

Open weights

Release Timeline

When each model was launched

Gemma 2 9B was released on 2024-06-27, while GPT OSS 20B was released on 2025-08-05.

GPT OSS 20B is 13 months newer than Gemma 2 9B.

Gemma 2 9B

Jun 27, 2024

2.0 years ago

GPT OSS 20B

Aug 5, 2025

10 months ago

1.1yr 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

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

OpenAI
Larger context window (131,072 tokens)
Higher MMLU score (85.3% vs 71.3%)

Detailed Comparison

AI Model Comparison Table
Feature
Google
Gemma 2 9B
OpenAI
GPT OSS 20B

FAQ

Common questions about Gemma 2 9B vs GPT OSS 20B.

Which is better, Gemma 2 9B or GPT OSS 20B?

GPT OSS 20B significantly outperforms across most benchmarks. Gemma 2 9B is made by Google and GPT OSS 20B is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemma 2 9B compare to GPT OSS 20B in benchmarks?

Gemma 2 9B scores ARC-E: 88.0%, BoolQ: 84.2%, HellaSwag: 81.9%, PIQA: 81.7%, Winogrande: 80.6%. GPT OSS 20B scores MMLU: 85.3%, CodeForces: 74.3%, GPQA: 71.5%, TAU-bench Retail: 54.8%, HealthBench: 42.5%.

What are the context window sizes for Gemma 2 9B and GPT OSS 20B?

Gemma 2 9B supports an unknown number of tokens and GPT OSS 20B supports 131K 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 9B and GPT OSS 20B?

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

Who makes Gemma 2 9B and GPT OSS 20B?

Gemma 2 9B is developed by Google and GPT OSS 20B is developed by OpenAI.

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