Model Comparison

Claude Sonnet 4 vs GPT-4.5Which is better in 2026?

Claude Sonnet 4 significantly outperforms across most benchmarks. Claude Sonnet 4 is 15.6x cheaper per token.

Verdict: Claude Sonnet 4 vs GPT-4.5 — which is better?

Claude Sonnet 4 (by Anthropic) and GPT-4.5 (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.

Claude Sonnet 4 outperforms in 5 benchmarks (GPQA, MMMLU, SWE-Bench Verified, TAU-bench Airline, TAU-bench Retail), while GPT-4.5 is better at 1 benchmark (MMMU). Claude Sonnet 4 significantly outperforms across most benchmarks.

On price, Claude Sonnet 4 is roughly 15.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Sonnet 4 also accepts a larger context window (200,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Claude Sonnet 4 if…

  • you want the strongest raw capability — it leads on 5 of 6 shared benchmarks
  • cost matters — it's about 15.6x cheaper per token
  • you process long inputs — it offers a 200,000 token context window
  • you want the most recent training data — it shipped May 2025

Choose GPT-4.5 if…

  • you want predictable pricing at $75.00/M input and $150.00/M output

Performance Benchmarks

Comparative analysis across standard metrics

6 benchmarks

Claude Sonnet 4 outperforms in 5 benchmarks (GPQA, MMMLU, SWE-Bench Verified, TAU-bench Airline, TAU-bench Retail), while GPT-4.5 is better at 1 benchmark (MMMU).

Claude Sonnet 4 significantly outperforms across most benchmarks.

Fri Jul 10 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Claude Sonnet 4 costs less

For input processing, Claude Sonnet 4 ($3.00/1M tokens) is 25.0x cheaper than GPT-4.5 ($75.00/1M tokens).

For output processing, Claude Sonnet 4 ($15.00/1M tokens) is 10.0x cheaper than GPT-4.5 ($150.00/1M tokens).

In conclusion, GPT-4.5 is more expensive than Claude Sonnet 4.*

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

Lowest available price from all providers
Fri Jul 10 2026 • llm-stats.com
Anthropic
Claude Sonnet 4
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
OpenAI
GPT-4.5
Input tokens$75.00
Output tokens$150.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Claude Sonnet 4 accepts 200,000 input tokens compared to GPT-4.5's 128,000 tokens. Claude Sonnet 4 can generate longer responses up to 64,000 tokens, while GPT-4.5 is limited to 4,096 tokens.

Anthropic
Claude Sonnet 4
Input200,000 tokens
Output64,000 tokens
OpenAI
GPT-4.5
Input128,000 tokens
Output4,096 tokens
Fri Jul 10 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Sonnet 4 and GPT-4.5 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-4.5

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-4.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 4 was released on 2025-05-22, while GPT-4.5 was released on 2025-02-27.

Claude Sonnet 4 is 3 months newer than GPT-4.5.

Claude Sonnet 4

May 22, 2025

1.1 years ago

2mo newer
GPT-4.5

Feb 27, 2025

1.4 years ago

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 Sonnet 4 is available from Anthropic, Bedrock, Google. GPT-4.5 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-4.5

openai logo
OpenAI
Input Price:Input: $75.00/1MOutput Price:Output: $150.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Larger context window (200,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher GPQA score (75.4% vs 69.5%)
Higher MMMLU score (86.5% vs 85.1%)
Higher SWE-Bench Verified score (72.7% vs 38.0%)
Higher TAU-bench Airline score (60.0% vs 50.0%)
Higher TAU-bench Retail score (80.5% vs 68.4%)
OpenAI
Higher MMMU score (75.2% vs 74.4%)
AnthropicClaude Sonnet 4
OpenAIGPT-4.5
Compare in Playground

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Claude Sonnet 4 and GPT-4.5 side-by-side, then vote on the output you prefer.

Claude Sonnet 4
✓ Preferred
GPT-4.5
Open in Playground
AI Model Comparison Table
Feature
Anthropic
Claude Sonnet 4
OpenAI
GPT-4.5

FAQ

Common questions about Claude Sonnet 4 vs GPT-4.5.

Which is better, Claude Sonnet 4 or GPT-4.5?

Claude Sonnet 4 significantly outperforms across most benchmarks. Claude Sonnet 4 is made by Anthropic and GPT-4.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Sonnet 4 compare to GPT-4.5 in benchmarks?

Claude Sonnet 4 scores MMMLU: 86.5%, TAU-bench Retail: 80.5%, GPQA: 75.4%, MMMU: 74.4%, SWE-Bench Verified: 72.7%. GPT-4.5 scores GSM8k: 97.0%, MMLU: 90.8%, CharXiv-D: 90.0%, IFEval: 88.2%, HumanEval: 88.0%.

Is Claude Sonnet 4 cheaper than GPT-4.5?

Claude Sonnet 4 is 25.0x cheaper for input tokens. Claude Sonnet 4 costs $3.00/M input and $15.00/M output via anthropic. GPT-4.5 costs $75.00/M input and $150.00/M output via openai.

What are the context window sizes for Claude Sonnet 4 and GPT-4.5?

Claude Sonnet 4 supports 200K tokens and GPT-4.5 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 Claude Sonnet 4 and GPT-4.5?

Key differences include context window (200K vs 128K), input pricing ($3.00 vs $75.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 4 and GPT-4.5?

Claude Sonnet 4 is developed by Anthropic and GPT-4.5 is developed by OpenAI.

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