Model Comparison
GLM-4.5 vs GPT-4.5Which is better in 2026?
GLM-4.5 significantly outperforms across most benchmarks. GLM-4.5 is 133.9x cheaper per token.
Verdict: GLM-4.5 vs GPT-4.5 — which is better?
GLM-4.5 (by Zhipu AI) and GPT-4.5 (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-4.5 outperforms in 5 benchmarks (AIME 2024, GPQA, SWE-Bench Verified, TAU-bench Airline, TAU-bench Retail), while GPT-4.5 is better at 0 benchmarks. GLM-4.5 significantly outperforms across most benchmarks.
On price, GLM-4.5 is roughly 133.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GLM-4.5 also accepts a larger context window (131,072 input tokens), making it the stronger choice for long documents and large codebases.
Choose GLM-4.5 if…
- you want the strongest raw capability — it leads on 5 of 5 shared benchmarks
- cost matters — it's about 133.9x cheaper per token
- you process long inputs — it offers a 131,072 token context window
- you want the most recent training data — it shipped Jul 2025
- you need open weights you can self-host or fine-tune
Choose GPT-4.5 if…
- you want predictable pricing at $75.00/M input and $150.00/M output
Performance Benchmarks
Comparative analysis across standard metrics
GLM-4.5 outperforms in 5 benchmarks (AIME 2024, GPQA, SWE-Bench Verified, TAU-bench Airline, TAU-bench Retail), while GPT-4.5 is better at 0 benchmarks.
GLM-4.5 significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Pricing Analysis
Price comparison per million tokens
For input processing, GLM-4.5 ($0.40/1M tokens) is 187.5x cheaper than GPT-4.5 ($75.00/1M tokens).
For output processing, GLM-4.5 ($1.60/1M tokens) is 93.8x cheaper than GPT-4.5 ($150.00/1M tokens).
In conclusion, GPT-4.5 is more expensive than GLM-4.5.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GLM-4.5 accepts 131,072 input tokens compared to GPT-4.5's 128,000 tokens. GLM-4.5 can generate longer responses up to 131,072 tokens, while GPT-4.5 is limited to 4,096 tokens.
Input Capabilities
Supported data types and modalities
GPT-4.5 supports multimodal inputs, whereas GLM-4.5 does not.
GPT-4.5 can handle both text and other forms of data like images, making it suitable for multimodal applications.
GLM-4.5
GPT-4.5
License
Usage and distribution terms
GLM-4.5 is licensed under MIT, while GPT-4.5 uses a proprietary license.
License differences may affect how you can use these models in commercial or open-source projects.
MIT
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
GLM-4.5 was released on 2025-07-28, while GPT-4.5 was released on 2025-02-27.
GLM-4.5 is 5 months newer than GPT-4.5.
Jul 28, 2025
11 months ago
5mo newerFeb 27, 2025
1.4 years ago
Knowledge Cutoff
When training data ends
Neither model specifies a knowledge cutoff date.
Unable to compare the recency of their training data.
Provider Availability
GLM-4.5 is available from DeepInfra, Fireworks, Novita. GPT-4.5 is available from OpenAI.
GLM-4.5
GPT-4.5
Outputs Comparison
Key Takeaways
GLM-4.5
View detailsZhipu AI
GPT-4.5
View detailsOpenAI
Detailed Comparison
Interactive Arena
Judge for yourself.
Run your own prompts against GLM-4.5 and GPT-4.5 side-by-side, then vote on the output you prefer.
FAQ
Common questions about GLM-4.5 vs GPT-4.5.