Model Comparison

GLM-5 vs GPT-5.6 LunaWhich is better in 2026?

GPT-5.6 Luna significantly outperforms across most benchmarks. GLM-5 is 1.5x cheaper per token.

Verdict: GLM-5 vs GPT-5.6 Luna — which is better?

GLM-5 (by Zhipu AI) and GPT-5.6 Luna (by OpenAI) 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.

GLM-5 outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 1 benchmark (BrowseComp). GPT-5.6 Luna significantly outperforms across most benchmarks.

On price, GLM-5 is roughly 1.5x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.6 Luna also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GLM-5 if…

  • cost matters — it's about 1.5x cheaper per token
  • you need open weights you can self-host or fine-tune

Choose GPT-5.6 Luna if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Jul 2026

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

GLM-5 outperforms in 0 benchmarks, while GPT-5.6 Luna is better at 1 benchmark (BrowseComp).

GPT-5.6 Luna significantly outperforms across most benchmarks.

Fri Jul 17 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) costs the same as GPT-5.6 Luna ($1.00/1M tokens).

For output processing, GLM-5 ($3.20/1M tokens) is 1.9x cheaper than GPT-5.6 Luna ($6.00/1M tokens).

In conclusion, GPT-5.6 Luna is more expensive than GLM-5.*

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

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Zhipu AI
GLM-5
Input tokens$1.00
Output tokens$3.20
Best providerFriendliAI
OpenAI
GPT-5.6 Luna
Input tokens$1.00
Output tokens$6.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.6 Luna 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-5.6 Luna
Input1,050,000 tokens
Output128,000 tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

GPT-5.6 Luna supports multimodal inputs, whereas GLM-5 does not.

GPT-5.6 Luna can handle both text and other forms of data like images, making it suitable for multimodal applications.

GLM-5

Text
Images
Audio
Video

GPT-5.6 Luna

Text
Images
Audio
Video

License

Usage and distribution terms

GLM-5 is licensed under MIT, while GPT-5.6 Luna 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-5.6 Luna

Proprietary

Closed source

Release Timeline

When each model was launched

GLM-5 was released on 2026-02-11, while GPT-5.6 Luna was released on 2026-07-09.

GPT-5.6 Luna is 5 months newer than GLM-5.

GLM-5

Feb 11, 2026

5 months ago

GPT-5.6 Luna

Jul 9, 2026

1 weeks ago

4mo newer

Knowledge Cutoff

When training data ends

GPT-5.6 Luna has a documented knowledge cutoff of 2026-02-16, while GLM-5's cutoff date is not specified.

We can confirm GPT-5.6 Luna's training data extends to 2026-02-16, but cannot make a direct comparison without GLM-5's cutoff date.

GLM-5

—

GPT-5.6 Luna

Feb 2026

Provider Availability

GLM-5 is available from FriendliAI, ZAI. GPT-5.6 Luna is available from OpenAI.

GLM-5

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

GPT-5.6 Luna

openai logo
OpenAI
Input Price:Input: $1.00/1MOutput Price:Output: $6.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Zhipu AI
Less expensive output tokens
Has open weights
OpenAI
Larger context window (1,050,000 tokens)
Supports multimodal inputs
Higher BrowseComp score (83.3% vs 75.9%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against GLM-5 and GPT-5.6 Luna side-by-side, then vote on the output you prefer.

GLM-5
✓ Preferred
GPT-5.6 Luna
Open in Playground
AI Model Comparison Table
Feature
Zhipu AI
GLM-5
OpenAI
GPT-5.6 Luna

FAQ

Common questions about GLM-5 vs GPT-5.6 Luna.

Which is better, GLM-5 or GPT-5.6 Luna?

GPT-5.6 Luna significantly outperforms across most benchmarks. GLM-5 is made by Zhipu AI and GPT-5.6 Luna 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-5.6 Luna 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-5.6 Luna scores Connectors: 99.9%, HealthBench Consensus: 95.1%, GPQA: 92.3%, Search and Function-Calling: 89.7%, Capture-the-Flag Challenges (Internal): 85.2%.

Is GLM-5 cheaper than GPT-5.6 Luna?

Both models cost $1.00 per million input tokens.

What are the context window sizes for GLM-5 and GPT-5.6 Luna?

GLM-5 supports 200K tokens and GPT-5.6 Luna 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-5.6 Luna?

Key differences include context window (200K vs 1.1M), 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-5.6 Luna?

GLM-5 is developed by Zhipu AI and GPT-5.6 Luna is developed by OpenAI.

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