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Claude 3.5 Sonnet vs GPT-4.5

GPT-4.5 shows notably better performance in the majority of benchmarks. Claude 3.5 Sonnet is 15.6x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude 3.5 Sonnet outperforms in 3 benchmarks (HumanEval, SWE-Bench Verified, TAU-bench Retail), while GPT-4.5 is better at 6 benchmarks (GPQA, GSM8k, MathVista, MMLU, MMMU, TAU-bench Airline). GPT-4.5 shows notably better performance in the majority of benchmarks.

On price, Claude 3.5 Sonnet is roughly 15.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude 3.5 Sonnet also accepts a larger context window (200,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current benchmark, pricing, and model metadata for 2026.

Choose Claude 3.5 Sonnet

  • cost matters — it's about 15.6x cheaper per token
  • you process long inputs — it offers a 200,000 token context window

Choose GPT-4.5

  • you want the strongest raw capability — it leads on 6 of 9 shared benchmarks
  • you want the most recent training data — it shipped Feb 2025

At a glance

The differences that matter most.

Benchmark wins
3 of 9
6 of 9
Input price
$3.00 / M
$75.00 / M
Output price
$15.00 / M
$150.00 / M
Context window
200,000
128,000
Released
Oct 2024
Feb 2025
License
Proprietary
Proprietary

Performance Benchmarks

Comparative analysis across standard metrics

9 benchmarks

Claude 3.5 Sonnet outperforms in 3 benchmarks (HumanEval, SWE-Bench Verified, TAU-bench Retail), while GPT-4.5 is better at 6 benchmarks (GPQA, GSM8k, MathVista, MMLU, MMMU, TAU-bench Airline).

GPT-4.5 shows notably better performance in the majority of benchmarks.

Mon Aug 24 2026 • llm-stats.com

Arena Performance

Playground indexes and blind preference scores

Pricing Analysis

Price comparison per million tokens

Claude 3.5 Sonnet costs less

For input processing, Claude 3.5 Sonnet ($3.00/1M tokens) is 25.0x cheaper than GPT-4.5 ($75.00/1M tokens).

For output processing, Claude 3.5 Sonnet ($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 3.5 Sonnet.*

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

Lowest available price from all providers
Mon Aug 24 2026 • llm-stats.com
Anthropic
Claude 3.5 Sonnet
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 3.5 Sonnet accepts 200,000 input tokens compared to GPT-4.5's 128,000 tokens. Claude 3.5 Sonnet can generate longer responses up to 200,000 tokens, while GPT-4.5 is limited to 4,096 tokens.

Anthropic
Claude 3.5 Sonnet
Input200,000 tokens
Output200,000 tokens
OpenAI
GPT-4.5
Input128,000 tokens
Output4,096 tokens
Mon Aug 24 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude 3.5 Sonnet and GPT-4.5 support multimodal inputs.

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

Claude 3.5 Sonnet

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 3.5 Sonnet

Proprietary

Closed source

GPT-4.5

Proprietary

Closed source

Release Timeline

When each model was launched

Claude 3.5 Sonnet was released on 2024-10-22, while GPT-4.5 was released on 2025-02-27.

GPT-4.5 is 4 months newer than Claude 3.5 Sonnet.

Claude 3.5 Sonnet

Oct 22, 2024

1.8 years ago

GPT-4.5

Feb 27, 2025

1.5 years ago

4mo 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 3.5 Sonnet is available from Anthropic, Bedrock, Google. GPT-4.5 is available from OpenAI.

Claude 3.5 Sonnet

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

Judge for yourself.

Run your own prompts against Claude 3.5 Sonnet and GPT-4.5 side-by-side, then vote on the output you prefer.

Claude 3.5 Sonnet
✓ Preferred
GPT-4.5
Open in Playground

FAQ

Common questions about Claude 3.5 Sonnet vs GPT-4.5.

Which is better, Claude 3.5 Sonnet or GPT-4.5?

GPT-4.5 shows notably better performance in the majority of benchmarks. Claude 3.5 Sonnet 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 3.5 Sonnet compare to GPT-4.5 in benchmarks?

Claude 3.5 Sonnet scores GSM8k: 96.4%, DocVQA: 95.2%, AI2D: 94.7%, HumanEval: 93.7%, BIG-Bench Hard: 93.1%. GPT-4.5 scores GSM8k: 97.0%, MMLU: 90.8%, CharXiv-D: 90.0%, IFEval: 88.2%, HumanEval: 88.0%.

Is Claude 3.5 Sonnet cheaper than GPT-4.5?

Claude 3.5 Sonnet is 25.0x cheaper for input tokens. Claude 3.5 Sonnet 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 3.5 Sonnet and GPT-4.5?

Claude 3.5 Sonnet 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 3.5 Sonnet 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 3.5 Sonnet and GPT-4.5?

Claude 3.5 Sonnet is developed by Anthropic and GPT-4.5 is developed by OpenAI.