Model Comparison

GPT OSS 20B vs Grok-4.1 ThinkingWhich is better in 2026?

Comparing GPT OSS 20B and Grok-4.1 Thinking across benchmarks, pricing, and capabilities.

Verdict: GPT OSS 20B vs Grok-4.1 Thinking — which is better?

GPT OSS 20B (by OpenAI) and Grok-4.1 Thinking (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.

On price, GPT OSS 20B is roughly 68.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok-4.1 Thinking also accepts a larger context window (256,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT OSS 20B if…

  • cost matters — it's about 68.6x cheaper per token
  • you need open weights you can self-host or fine-tune

Choose Grok-4.1 Thinking if…

  • you process long inputs — it offers a 256,000 token context window
  • you want the most recent training data — it shipped Nov 2025

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT OSS 20B and Grok-4.1 Thinkingdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT OSS 20B costs less

For input processing, GPT OSS 20B ($0.05/1M tokens) is 60.0x cheaper than Grok-4.1 Thinking ($3.00/1M tokens).

For output processing, GPT OSS 20B ($0.20/1M tokens) is 75.0x cheaper than Grok-4.1 Thinking ($15.00/1M tokens).

In conclusion, Grok-4.1 Thinking is more expensive than GPT OSS 20B.*

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

Lowest available price from all providers
Sun Jul 26 2026 • llm-stats.com
OpenAI
GPT OSS 20B
Input tokens$0.05
Output tokens$0.20
Best providerNovita
xAI
Grok-4.1 Thinking
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

Grok-4.1 Thinking accepts 256,000 input tokens compared to GPT OSS 20B's 131,072 tokens. GPT OSS 20B can generate longer responses up to 32,768 tokens, while Grok-4.1 Thinking is limited to 8,000 tokens.

OpenAI
GPT OSS 20B
Input131,072 tokens
Output32,768 tokens
xAI
Grok-4.1 Thinking
Input256,000 tokens
Output8,000 tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Grok-4.1 Thinking supports multimodal inputs, whereas GPT OSS 20B does not.

Grok-4.1 Thinking can handle both text and other forms of data like images, making it suitable for multimodal applications.

GPT OSS 20B

Text
Images
Audio
Video

Grok-4.1 Thinking

Text
Images
Audio
Video

License

Usage and distribution terms

GPT OSS 20B is licensed under Apache 2.0, while Grok-4.1 Thinking uses a proprietary license.

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

GPT OSS 20B

Apache 2.0

Open weights

Grok-4.1 Thinking

Proprietary

Closed source

Release Timeline

When each model was launched

GPT OSS 20B was released on 2025-08-05, while Grok-4.1 Thinking was released on 2025-11-17.

Grok-4.1 Thinking is 3 months newer than GPT OSS 20B.

GPT OSS 20B

Aug 5, 2025

11 months ago

Grok-4.1 Thinking

Nov 17, 2025

8 months ago

3mo 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

Provider Availability

GPT OSS 20B is available from Novita, Fireworks, Groq, OpenAI. Grok-4.1 Thinking is available from xAI.

GPT OSS 20B

novita logo
Novita
Input Price:Input: $0.05/1MOutput Price:Output: $0.20/1M
fireworks logo
Fireworks
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
groq logo
Groq
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

Grok-4.1 Thinking

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

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Less expensive input tokens
Less expensive output tokens
Has open weights
xAI
Larger context window (256,000 tokens)
Supports multimodal inputs

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT OSS 20B and Grok-4.1 Thinking side-by-side, then vote on the output you prefer.

GPT OSS 20B
✓ Preferred
Grok-4.1 Thinking
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT OSS 20B
xAI
Grok-4.1 Thinking

FAQ

Common questions about GPT OSS 20B vs Grok-4.1 Thinking.

Which is better, GPT OSS 20B or Grok-4.1 Thinking?

GPT OSS 20B (OpenAI) and Grok-4.1 Thinking (xAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GPT OSS 20B compare to Grok-4.1 Thinking in benchmarks?

GPT OSS 20B scores MMLU: 85.3%, CodeForces: 74.3%, GPQA: 71.5%, TAU-bench Retail: 54.8%, HealthBench: 42.5%. Grok-4.1 Thinking scores Creative Writing v3: 86.1%, WMDP: 84.0%, EQ-Bench: 79.3%, ProtocolQA: 79.0%, LMArena Text Leaderboard: 74.2%.

Is GPT OSS 20B cheaper than Grok-4.1 Thinking?

GPT OSS 20B is 60.0x cheaper for input tokens. GPT OSS 20B costs $0.05/M input and $0.20/M output via novita. Grok-4.1 Thinking costs $3.00/M input and $15.00/M output via xai.

What are the context window sizes for GPT OSS 20B and Grok-4.1 Thinking?

GPT OSS 20B supports 131K tokens and Grok-4.1 Thinking 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 OSS 20B and Grok-4.1 Thinking?

Key differences include context window (131K vs 256K), input pricing ($0.05 vs $3.00/M), multimodal support (no vs yes), licensing (Apache 2.0 vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT OSS 20B and Grok-4.1 Thinking?

GPT OSS 20B is developed by OpenAI and Grok-4.1 Thinking is developed by xAI.

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