Model Comparison

GLM-5 vs GPT-5.5

GPT-5.5 significantly outperforms across most benchmarks. GLM-5 is 7.3x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

3 benchmarks

GLM-5 outperforms in 0 benchmarks, while GPT-5.5 is better at 3 benchmarks (BrowseComp, MCP Atlas, Terminal-Bench 2.0).

GPT-5.5 significantly outperforms across most benchmarks.

Wed May 13 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

GLM-5 costs less

For input processing, GLM-5 ($1.00/1M tokens) is 5.0x cheaper than GPT-5.5 ($5.00/1M tokens).

For output processing, GLM-5 ($3.20/1M tokens) is 9.4x cheaper than GPT-5.5 ($30.00/1M tokens).

In conclusion, GPT-5.5 is more expensive than GLM-5.*

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

Lowest available price from all providers
Wed May 13 2026 • llm-stats.com
Zhipu AI
GLM-5
Input tokens$1.00
Output tokens$3.20
Best providerUnknown Organization
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.5 accepts 1,050,000 input tokens compared to GLM-5's 200,000 tokens. Both models can generate responses up to 128,000 tokens.

Zhipu AI
GLM-5
Input200,000 tokens
Output128,000 tokens
OpenAI
GPT-5.5
Input1,050,000 tokens
Output128,000 tokens
Wed May 13 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5.5 supports multimodal inputs, whereas GLM-5 does not.

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

GLM-5

Text
Images
Audio
Video

GPT-5.5

Text
Images
Audio
Video

License

Usage and distribution terms

GLM-5 is licensed under MIT, while GPT-5.5 uses a proprietary license.

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

GLM-5

MIT

Open weights

GPT-5.5

Proprietary

Closed source

Release Timeline

When each model was launched

GLM-5 was released on 2026-02-11, while GPT-5.5 was released on 2026-04-23.

GPT-5.5 is 2 months newer than GLM-5.

GLM-5

Feb 11, 2026

3 months ago

GPT-5.5

Apr 23, 2026

2 weeks ago

2mo newer

Knowledge Cutoff

When training data ends

GPT-5.5 has a documented knowledge cutoff of 2025-12-01, while GLM-5's cutoff date is not specified.

We can confirm GPT-5.5's training data extends to 2025-12-01, but cannot make a direct comparison without GLM-5's cutoff date.

GLM-5

—

GPT-5.5

Dec 2025

Provider Availability

GLM-5 is available from ZAI. GPT-5.5 is available from OpenAI.

GLM-5

z logo
Unknown Organization
Input Price:Input: $1.00/1MOutput Price:Output: $3.20/1M

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

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Key Takeaways

Zhipu AI
Less expensive input tokens
Less expensive output tokens
Has open weights
OpenAI
Larger context window (1,050,000 tokens)
Supports multimodal inputs
Higher BrowseComp score (84.4% vs 75.9%)
Higher MCP Atlas score (75.3% vs 67.8%)
Higher Terminal-Bench 2.0 score (82.7% vs 56.2%)

Detailed Comparison

AI Model Comparison Table
Feature
Zhipu AI
GLM-5
OpenAI
GPT-5.5

FAQ

Common questions about GLM-5 vs GPT-5.5.

Which is better, GLM-5 or GPT-5.5?

GPT-5.5 significantly outperforms across most benchmarks. GLM-5 is made by Zhipu AI and GPT-5.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GLM-5 compare to GPT-5.5 in benchmarks?

GLM-5 scores t2-bench: 89.7%, SWE-Bench Verified: 77.8%, BrowseComp: 75.9%, MCP Atlas: 67.8%, Terminal-Bench 2.0: 56.2%. GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%.

Is GLM-5 cheaper than GPT-5.5?

GLM-5 is 5.0x cheaper for input tokens. GLM-5 costs $1.00/M input and $3.20/M output via z. GPT-5.5 costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for GLM-5 and GPT-5.5?

GLM-5 supports 200K tokens and GPT-5.5 supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GLM-5 and GPT-5.5?

Key differences include context window (200K vs 1.1M), input pricing ($1.00 vs $5.00/M), multimodal support (no vs yes), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.

Who makes GLM-5 and GPT-5.5?

GLM-5 is developed by Zhipu AI and GPT-5.5 is developed by OpenAI.