Model Comparison

Claude Opus 4 vs GPT OSS 20B High

Both models are evenly matched across the benchmarks. GPT OSS 20B High is 150.0x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Claude Opus 4 outperforms in 1 benchmarks (GPQA), while GPT OSS 20B High is better at 1 benchmark (AIME 2025).

Both models are evenly matched across the benchmarks.

Tue Apr 21 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT OSS 20B High costs less

For input processing, Claude Opus 4 ($15.00/1M tokens) is 150.0x more expensive than GPT OSS 20B High ($0.10/1M tokens).

For output processing, Claude Opus 4 ($75.00/1M tokens) is 150.0x more expensive than GPT OSS 20B High ($0.50/1M tokens).

In conclusion, Claude Opus 4 is more expensive than GPT OSS 20B High.*

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

Lowest available price from all providers
Tue Apr 21 2026 • llm-stats.com
Anthropic
Claude Opus 4
Input tokens$15.00
Output tokens$75.00
Best providerAnthropic
OpenAI
GPT OSS 20B High
Input tokens$0.10
Output tokens$0.50
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Opus 4 accepts 200,000 input tokens compared to GPT OSS 20B High's 131,072 tokens. GPT OSS 20B High can generate longer responses up to 131,072 tokens, while Claude Opus 4 is limited to 32,000 tokens.

Anthropic
Claude Opus 4
Input200,000 tokens
Output32,000 tokens
OpenAI
GPT OSS 20B High
Input131,072 tokens
Output131,072 tokens
Tue Apr 21 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Claude Opus 4 supports multimodal inputs, whereas GPT OSS 20B High does not.

Claude Opus 4 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Opus 4

Text
Images
Audio
Video

GPT OSS 20B High

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Opus 4 is licensed under a proprietary license, while GPT OSS 20B High uses Apache 2.0.

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

Claude Opus 4

Proprietary

Closed source

GPT OSS 20B High

Apache 2.0

Open weights

Release Timeline

When each model was launched

Claude Opus 4 was released on 2025-05-22, while GPT OSS 20B High was released on 2025-08-05.

GPT OSS 20B High is 3 months newer than Claude Opus 4.

Claude Opus 4

May 22, 2025

11 months ago

GPT OSS 20B High

Aug 5, 2025

8 months 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

Provider Availability

Claude Opus 4 is available from Anthropic, Bedrock, Google. GPT OSS 20B High is available from OpenAI.

Claude Opus 4

anthropic logo
Anthropic
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M
google logo
Google
Input Price:Input: $15.00/1MOutput Price:Output: $75.00/1M

GPT OSS 20B High

openai logo
OpenAI
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Supports multimodal inputs
Higher GPQA score (79.6% vs 74.2%)
OpenAI
Less expensive input tokens
Less expensive output tokens
Has open weights
Higher AIME 2025 score (98.7% vs 75.5%)
AnthropicClaude Opus 4
OpenAIGPT OSS 20B High
Compare in Playground

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4
OpenAI
GPT OSS 20B High

FAQ

Common questions about Claude Opus 4 vs GPT OSS 20B High

Both models are evenly matched across the benchmarks. Claude Opus 4 is made by Anthropic and GPT OSS 20B High is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.
Claude Opus 4 scores MMMLU: 88.8%, TAU-bench Retail: 81.4%, GPQA: 79.6%, MMMU (validation): 76.5%, AIME 2025: 75.5%. GPT OSS 20B High scores AIME 2025: 98.7%, GPQA: 74.2%.
GPT OSS 20B High is 150.0x cheaper for input tokens. Claude Opus 4 costs $15.00/M input and $75.00/M output via anthropic. GPT OSS 20B High costs $0.10/M input and $0.50/M output via openai.
Claude Opus 4 supports 200K tokens and GPT OSS 20B High supports 131K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include context window (200K vs 131K), input pricing ($15.00 vs $0.10/M), multimodal support (yes vs no), licensing (Proprietary vs Apache 2.0). See the full comparison above for benchmark-by-benchmark results.
Claude Opus 4 is developed by Anthropic and GPT OSS 20B High is developed by OpenAI.