Model Comparison

GPT-5 vs Claude Sonnet 4.5Which is better in 2026?

GPT-5 significantly outperforms across most benchmarks. GPT-5 is 1.7x cheaper per token.

Verdict: GPT-5 vs Claude Sonnet 4.5 — which is better?

GPT-5 (by OpenAI) and Claude Sonnet 4.5 (by Anthropic) 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.

GPT-5 outperforms in 2 benchmarks (AIME 2025, GPQA), while Claude Sonnet 4.5 is better at 0 benchmarks. GPT-5 significantly outperforms across most benchmarks.

On price, GPT-5 is roughly 1.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5 also accepts a larger context window (400,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-5 if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • cost matters — it's about 1.7x cheaper per token
  • you process long inputs — it offers a 400,000 token context window

Choose Claude Sonnet 4.5 if…

  • you want the most recent training data — it shipped Sep 2025

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

GPT-5 outperforms in 2 benchmarks (AIME 2025, GPQA), while Claude Sonnet 4.5 is better at 0 benchmarks.

GPT-5 significantly outperforms across most benchmarks.

Sun Jul 05 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GPT-5 costs less

For input processing, GPT-5 ($1.25/1M tokens) is 2.4x cheaper than Claude Sonnet 4.5 ($3.00/1M tokens).

For output processing, GPT-5 ($10.00/1M tokens) is 1.5x cheaper than Claude Sonnet 4.5 ($15.00/1M tokens).

In conclusion, Claude Sonnet 4.5 is more expensive than GPT-5.*

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

Lowest available price from all providers
Sun Jul 05 2026 • llm-stats.com
OpenAI
GPT-5
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Anthropic
Claude Sonnet 4.5
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5 accepts 400,000 input tokens compared to Claude Sonnet 4.5's 200,000 tokens. GPT-5 can generate longer responses up to 128,000 tokens, while Claude Sonnet 4.5 is limited to 64,000 tokens.

OpenAI
GPT-5
Input400,000 tokens
Output128,000 tokens
Anthropic
Claude Sonnet 4.5
Input200,000 tokens
Output64,000 tokens
Sun Jul 05 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5 and Claude Sonnet 4.5 support multimodal inputs.

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

GPT-5

Text
Images
Audio
Video

Claude Sonnet 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.

GPT-5

Proprietary

Closed source

Claude Sonnet 4.5

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5 was released on 2025-08-07, while Claude Sonnet 4.5 was released on 2025-09-29.

Claude Sonnet 4.5 is 2 months newer than GPT-5.

GPT-5

Aug 7, 2025

11 months ago

Claude Sonnet 4.5

Sep 29, 2025

9 months ago

1mo newer

Knowledge Cutoff

When training data ends

GPT-5 has a knowledge cutoff of 2024-09-30, while Claude Sonnet 4.5 has a cutoff of 2025-01-31.

Claude Sonnet 4.5 has more recent training data (up to 2025-01-31), making it potentially better informed about events through that date compared to GPT-5 (2024-09-30).

GPT-5

Sep 2024

Claude Sonnet 4.5

Jan 2025

4 mo newer

Provider Availability

GPT-5 is available from OpenAI. Claude Sonnet 4.5 is available from Anthropic.

GPT-5

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M

Claude Sonnet 4.5

anthropic logo
Anthropic
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
Larger context window (400,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher AIME 2025 score (94.6% vs 87.0%)
Higher GPQA score (85.7% vs 83.4%)
Anthropic

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

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GPT-5 and Claude Sonnet 4.5 side-by-side, then vote on the output you prefer.

GPT-5
✓ Preferred
Claude Sonnet 4.5
Open in Playground
AI Model Comparison Table
Feature
OpenAI
GPT-5
Anthropic
Claude Sonnet 4.5

FAQ

Common questions about GPT-5 vs Claude Sonnet 4.5.

Which is better, GPT-5 or Claude Sonnet 4.5?

GPT-5 significantly outperforms across most benchmarks. GPT-5 is made by OpenAI and Claude Sonnet 4.5 is made by Anthropic. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5 compare to Claude Sonnet 4.5 in benchmarks?

GPT-5 scores SWE-Lancer (IC-Diamond subset): 100.0%, COLLIE: 99.0%, Tau2 Telecom: 96.7%, OpenAI-MRCR: 2 needle 128k: 95.2%, AIME 2025: 94.6%. Claude Sonnet 4.5 scores MMMLU: 89.1%, AIME 2025: 87.0%, TAU-bench Retail: 86.2%, GPQA: 83.4%, MMMUval: 77.8%.

Is GPT-5 cheaper than Claude Sonnet 4.5?

GPT-5 is 2.4x cheaper for input tokens. GPT-5 costs $1.25/M input and $10.00/M output via openai. Claude Sonnet 4.5 costs $3.00/M input and $15.00/M output via anthropic.

What are the context window sizes for GPT-5 and Claude Sonnet 4.5?

GPT-5 supports 400K tokens and Claude Sonnet 4.5 supports 200K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5 and Claude Sonnet 4.5?

Key differences include context window (400K vs 200K), input pricing ($1.25 vs $3.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5 and Claude Sonnet 4.5?

GPT-5 is developed by OpenAI and Claude Sonnet 4.5 is developed by Anthropic.

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