GLM-4.5Open Weight
GLM-4.5 is an AI model released by Z.ai on Monday, Jul 28 2025, 333 days after GLM-4-Plus. It is an open-weight model — the trained weights are available to download and run. It is a 355B parameter model with a 128k token context window. Benchmark results (shown below) cover BullshitBench v2, SWE-Bench Verified, and GPQA Diamond.
Benchmarks
About GLM-4.5
GLM-4.5, released July 28, 2025 alongside the lighter GLM-4.5-Air, was Z.ai's entry into the open-weight frontier race: a 355B-parameter mixture-of-experts model designed explicitly for agentic tasks, unifying reasoning, coding, and tool use with switchable thinking modes. It scored 79.1% on GPQA and 64.2% on SWE-Bench Verified.
Released the same month as Kimi K2, it was part of the mid-2025 wave of Chinese open-weight agentic models that reset expectations for what freely downloadable weights could do. Its low-cost API and coding-agent integrations won it a significant developer following outside China, and GLM-4.6 followed nine weeks later.
GLM-4.5 — frequently asked questions
- When was GLM-4.5 released?
- GLM-4.5 was released by Z.ai on Monday, Jul 28 2025.
- Who made GLM-4.5?
- GLM-4.5 was built by Z.ai. Chinese AI lab spun out of Tsinghua University (formerly Zhipu AI), building the open-weight GLM family. Rebranded internationally as Z.ai in 2025.
- What benchmark scores did GLM-4.5 get?
- GLM-4.5 reports 3 tracked benchmark scores — BullshitBench v2: 8%; SWE-Bench Verified: 64.2%; GPQA Diamond: 79.1%. Scores are the figures published at release by Z.ai.
- What is the context window of GLM-4.5?
- GLM-4.5 has a context window of 128k. That is the maximum amount of input plus output the model can hold in a single request.
- How many parameters does GLM-4.5 have?
- GLM-4.5 is reported at 355B parameters.
- Is GLM-4.5 open source?
- Partly. GLM-4.5 is an open-weight model: the trained weights are free to download and run locally or on your own infrastructure, but the training data and code are not fully released and the license may restrict some commercial uses. It is not open source in the strict sense.
- What came before and after GLM-4.5?
- Z.ai's previous tracked release was GLM-4-Plus on Aug 29 2024, 333 days earlier. It was followed by GLM-4.5-Air on Jul 28 2025.