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Model Comparison

GLM-5 vs GPT-5.5 Pro

GPT-5.5 Pro significantly outperforms across most benchmarks. GLM-5 is 43.5x cheaper per token.

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Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

GLM-5 outperforms in 0 benchmarks, while GPT-5.5 Pro is better at 1 benchmark (BrowseComp).

GPT-5.5 Pro significantly outperforms across most benchmarks.

Thu Apr 23 2026 • llm-stats.com

Arena Performance

Human preference votes

CallingBox

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One API for outbound and inbound calls.

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$0.05 /min all-in7 lines of code

Pricing Analysis

Price comparison per million tokens

GLM-5 costs less

For input processing, GLM-5 ($1.00/1M tokens) is 30.0x cheaper than GPT-5.5 Pro ($30.00/1M tokens).

For output processing, GLM-5 ($3.20/1M tokens) is 56.3x cheaper than GPT-5.5 Pro ($180.00/1M tokens).

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

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

Lowest available price from all providers
Thu Apr 23 2026 • llm-stats.com
Zhipu AI
GLM-5
Input tokens$1.00
Output tokens$3.20
Best providerUnknown Organization
OpenAI
GPT-5.5 Pro
Input tokens$30.00
Output tokens$180.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.5 Pro accepts 1,000,000 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 Pro
Input1,000,000 tokens
Output128,000 tokens
Thu Apr 23 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

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

GPT-5.5 Pro 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 Pro

Text
Images
Audio
Video

License

Usage and distribution terms

GLM-5 is licensed under MIT, while GPT-5.5 Pro 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 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

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

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

GLM-5

Feb 11, 2026

2 months ago

GPT-5.5 Pro

Apr 23, 2026

0 days ago

2mo 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

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

GLM-5

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

GPT-5.5 Pro

openai logo
OpenAI
Input Price:Input: $30.00/1MOutput Price:Output: $180.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Zhipu AI
Less expensive input tokens
Less expensive output tokens
Has open weights
OpenAI
Larger context window (1,000,000 tokens)
Supports multimodal inputs
Higher BrowseComp score (90.1% vs 75.9%)

Detailed Comparison

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

FAQ

Common questions about GLM-5 vs GPT-5.5 Pro

GPT-5.5 Pro significantly outperforms across most benchmarks. GLM-5 is made by Zhipu AI and GPT-5.5 Pro is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.
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 Pro scores BrowseComp: 90.1%, GDPval-MM: 82.3%, Humanity's Last Exam: 57.2%, FrontierMath: 39.6%, GeneBench: 33.2%.
GLM-5 is 30.0x cheaper for input tokens. GLM-5 costs $1.00/M input and $3.20/M output via z. GPT-5.5 Pro costs $30.00/M input and $180.00/M output via openai.
GLM-5 supports 200K tokens and GPT-5.5 Pro supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.
Key differences include context window (200K vs 1.0M), input pricing ($1.00 vs $30.00/M), multimodal support (no vs yes), licensing (MIT vs Proprietary). See the full comparison above for benchmark-by-benchmark results.
GLM-5 is developed by Zhipu AI and GPT-5.5 Pro is developed by OpenAI.