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Claude Sonnet 5.5 vs GLM-4.5

Claude Sonnet 5.5 leads the LLM Stats Score 58.0 to 27.7. GLM-4.5 is 5.7x cheaper per token.

Anthropic · Zhipu AI · Updated for 2026

Which is better?

Claude Sonnet 5.5 leads the overall LLM Stats Score 58.0 to 27.7, ranking #3 overall.

On price, GLM-4.5 is roughly 5.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Sonnet 5.5 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Sonnet 5.5

  • overall performance matters — it scores 58.0 and ranks #3 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose GLM-4.5

  • cost matters — it's about 5.7x cheaper per token
  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

Claude Sonnet 5.5
Anthropic
GLM-4.5
Zhipu AI
Core performance indexes
LLM Stats Score
58.0
#3
27.7
#148
Reasoning
56.6
#3
27.1
#148
Coding
48.8
#2
16.0
#135
Agents
42.3
#3
9.8
#128
Cost, coverage & limits
Benchmark wins
—
—
Input price
$2.00 / M
$0.40 / M
Output price
$10.00 / M
$1.60 / M
Context window
1,000,000
131,072

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Sonnet 5.5
GLM-4.5
Math
36.9#34
27.0#102
Tool use
34.0#2
21.3#54
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

47 reported for Claude Sonnet 5.5 · 14 for GLM-4.5

No common benchmarks found

Claude Sonnet 5.5 and GLM-4.5don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

GLM-4.5 costs less

For input processing, Claude Sonnet 5.5 ($2.00/1M tokens) is 5.0x more expensive than GLM-4.5 ($0.40/1M tokens).

For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) is 6.3x more expensive than GLM-4.5 ($1.60/1M tokens).

In conclusion, Claude Sonnet 5.5 is more expensive than GLM-4.5.*

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

Lowest available price from all providers
Thu Oct 01 2026 • llm-stats.com
Anthropic
Claude Sonnet 5.5
Input tokens$2.00
Output tokens$10.00
Best providerAnthropic
Zhipu AI
GLM-4.5
Input tokens$0.40
Output tokens$1.60
Best providerDeepinfra
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Claude Sonnet 5.5 accepts 1,000,000 input tokens compared to GLM-4.5's 131,072 tokens. GLM-4.5 can generate longer responses up to 131,072 tokens, while Claude Sonnet 5.5 is limited to 128,000 tokens.

Anthropic
Claude Sonnet 5.5
Input1,000,000 tokens
Output128,000 tokens
Zhipu AI
GLM-4.5
Input131,072 tokens
Output131,072 tokens
Thu Oct 01 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Claude Sonnet 5.5 supports multimodal inputs, whereas GLM-4.5 does not.

Claude Sonnet 5.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.

Claude Sonnet 5.5

Text
Images
Audio
Video

GLM-4.5

Text
Images
Audio
Video

License

Usage and distribution terms

Claude Sonnet 5.5 is licensed under a proprietary license, while GLM-4.5 uses MIT.

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

Claude Sonnet 5.5

Proprietary

Closed source

GLM-4.5

MIT

Open weights

Release Timeline

When each model was launched

Claude Sonnet 5.5 was released on 2026-09-28, while GLM-4.5 was released on 2025-07-28.

Claude Sonnet 5.5 is 14 months newer than GLM-4.5.

Claude Sonnet 5.5

Sep 28, 2026

2 days ago

1.2yr newer
GLM-4.5

Jul 28, 2025

1.2 years ago

Knowledge Cutoff

When training data ends

Claude Sonnet 5.5 has a documented knowledge cutoff of 2026-06-01, while GLM-4.5's cutoff date is not specified.

We can confirm Claude Sonnet 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without GLM-4.5's cutoff date.

Claude Sonnet 5.5

Jun 2026

GLM-4.5

—

Provider Availability

Claude Sonnet 5.5 is available from Anthropic. GLM-4.5 is available from DeepInfra, Fireworks, Novita.

Claude Sonnet 5.5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M

GLM-4.5

deepinfra logo
Deepinfra
Input Price:Input: $0.40/1MOutput Price:Output: $1.60/1M
fireworks logo
Fireworks
Input Price:Input: $0.55/1MOutput Price:Output: $2.19/1M
novita logo
Novita
Input Price:Input: $0.60/1MOutput Price:Output: $2.20/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Sonnet 5.5 and GLM-4.5 side-by-side, then vote on the output you prefer.

Claude Sonnet 5.5
✓ Preferred
GLM-4.5
Open in Playground

FAQ

Common questions about Claude Sonnet 5.5 vs GLM-4.5.

Which is better, Claude Sonnet 5.5 or GLM-4.5?

Claude Sonnet 5.5 leads the LLM Stats Score 58.0 to 27.7. Claude Sonnet 5.5 is made by Anthropic and GLM-4.5 is made by Zhipu AI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Sonnet 5.5 compare to GLM-4.5 in benchmarks?

Claude Sonnet 5.5 scores BenchCAD (with Python tool): 96.3%, ArXivMath (with tools): 95.2%, Global-MMLU: 92.1%, MILU: 91.6%, SWE-bench Multilingual: 90.3%. GLM-4.5 scores MATH-500: 98.2%, AIME 2024: 91.0%, MMLU-Pro: 84.6%, TAU-bench Retail: 79.7%, GPQA: 79.1%.

Is Claude Sonnet 5.5 cheaper than GLM-4.5?

GLM-4.5 is 5.0x cheaper for input tokens. Claude Sonnet 5.5 costs $2.00/M input and $10.00/M output via anthropic. GLM-4.5 costs $0.40/M input and $1.60/M output via deepinfra.

What are the context window sizes for Claude Sonnet 5.5 and GLM-4.5?

Claude Sonnet 5.5 supports 1.0M tokens and GLM-4.5 supports 131K 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 5.5 and GLM-4.5?

Key differences include LLM Stats Score (58.0 vs 27.7), context window (1.0M vs 131K), input pricing ($2.00 vs $0.40/M), multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Sonnet 5.5 and GLM-4.5?

Claude Sonnet 5.5 is developed by Anthropic and GLM-4.5 is developed by Zhipu AI.

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