Model Comparison

Claude Sonnet 4 vs GPT-5.1

GPT-5.1 significantly outperforms across most benchmarks. GPT-5.1 is 1.7x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

4 benchmarks

Claude Sonnet 4 outperforms in 0 benchmarks, while GPT-5.1 is better at 4 benchmarks (AIME 2025, GPQA, MMMU, SWE-Bench Verified).

GPT-5.1 significantly outperforms across most benchmarks.

Tue Apr 14 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5.1 costs less

For input processing, Claude Sonnet 4 ($3.00/1M tokens) is 2.4x more expensive than GPT-5.1 ($1.25/1M tokens).

For output processing, Claude Sonnet 4 ($15.00/1M tokens) is 1.5x more expensive than GPT-5.1 ($10.00/1M tokens).

In conclusion, Claude Sonnet 4 is more expensive than GPT-5.1.*

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

Lowest available price from all providers
Tue Apr 14 2026 • llm-stats.com
Anthropic
Claude Sonnet 4
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
OpenAI
GPT-5.1
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.1 accepts 400,000 input tokens compared to Claude Sonnet 4's 200,000 tokens. GPT-5.1 can generate longer responses up to 128,000 tokens, while Claude Sonnet 4 is limited to 64,000 tokens.

Anthropic
Claude Sonnet 4
Input200,000 tokens
Output64,000 tokens
OpenAI
GPT-5.1
Input400,000 tokens
Output128,000 tokens
Tue Apr 14 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Sonnet 4 and GPT-5.1 support multimodal inputs.

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

Claude Sonnet 4

Text
Images
Audio
Video

GPT-5.1

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Sonnet 4

Proprietary

Closed source

GPT-5.1

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 4 was released on 2025-05-22, while GPT-5.1 was released on 2025-11-13.

GPT-5.1 is 6 months newer than Claude Sonnet 4.

Claude Sonnet 4

May 22, 2025

10 months ago

GPT-5.1

Nov 13, 2025

5 months ago

5mo newer

Knowledge Cutoff

When training data ends

GPT-5.1 has a documented knowledge cutoff of 2024-09-30, while Claude Sonnet 4's cutoff date is not specified.

We can confirm GPT-5.1's training data extends to 2024-09-30, but cannot make a direct comparison without Claude Sonnet 4's cutoff date.

Claude Sonnet 4

—

GPT-5.1

Sep 2024

Provider Availability

Claude Sonnet 4 is available from Anthropic, Bedrock, Google. GPT-5.1 is available from OpenAI.

Claude Sonnet 4

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
google logo
Google
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

GPT-5.1

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
OpenAI
Larger context window (400,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher AIME 2025 score (94.0% vs 70.5%)
Higher GPQA score (88.1% vs 75.4%)
Higher MMMU score (85.4% vs 74.4%)
Higher SWE-Bench Verified score (76.3% vs 72.7%)
AnthropicClaude Sonnet 4
OpenAIGPT-5.1
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Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Sonnet 4
OpenAI
GPT-5.1

FAQ

Common questions about Claude Sonnet 4 vs GPT-5.1

GPT-5.1 significantly outperforms across most benchmarks. Claude Sonnet 4 is made by Anthropic and GPT-5.1 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.
Claude Sonnet 4 scores MMMLU: 86.5%, TAU-bench Retail: 80.5%, GPQA: 75.4%, MMMU: 74.4%, SWE-Bench Verified: 72.7%. GPT-5.1 scores Tau2 Telecom: 95.6%, AIME 2025: 94.0%, BrowseComp Long Context 128k: 90.0%, GPQA: 88.1%, MMMU: 85.4%.
GPT-5.1 is 2.4x cheaper for input tokens. Claude Sonnet 4 costs $3.00/M input and $15.00/M output via anthropic. GPT-5.1 costs $1.25/M input and $10.00/M output via openai.
Claude Sonnet 4 supports 200K tokens and GPT-5.1 supports 400K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include context window (200K vs 400K), input pricing ($3.00 vs $1.25/M). See the full comparison above for benchmark-by-benchmark results.
Claude Sonnet 4 is developed by Anthropic and GPT-5.1 is developed by OpenAI.