# GLM-5.3-Flash GLM-5.3-Flash is an AI model released by Z.ai on Aug 26 2026. It has 320B parameters, a 1M context window and open weight. At release it scored 48.8% on AutomationBench, 84.3% on Terminal-Bench 2.1 and 55.3% on Humanity's Last Exam (with tools). ## Facts | Field | Value | | --- | --- | | Model | GLM-5.3-Flash | | Developer | Z.ai | | Release date | Wednesday, Aug 26 2026 | | Licensing | Open Weight | | Parameters | 320B | | Context window | 1M | ## Benchmark scores published at release | Benchmark | Score | Source | What it measures | | --- | --- | --- | --- | | DeepSWE 1.1 | 63.4% | Lab | Artificial Analysis' independent test of deep, agentic software-engineering work — the AI has to plan and carry out substantial coding tasks end to end. (Version 1.1 of the test.) Higher is better. | | Terminal-Bench 2.1 | 84.3% | Lab | Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Higher is better. | | Humanity's Last Exam (with tools) | 55.3% | Lab | Humanity's Last Exam — extremely hard expert questions across many subjects. “With tools” means the AI is allowed to search the web or run code while answering. Higher is better. | | Agent's Last Exam (pass@1) | 26.3% | Lab | A hard set of desktop and operating-system tasks an AI agent has to finish by looking at the screen and working the machine itself. The score is the share it passes outright — partial credit does not count. Higher is better. | | AutomationBench | 48.8% | Lab | Tests whether the AI can run real multi-step business workflows — the kind of end-to-end office processes companies want to automate — from start to finish. Higher is better. | | GDPval-AA v2 | 1773 | Lab | economically valuable knowledge work (v2, re-based Elo) | ## About GLM-5.3-Flash GLM-5.3-Flash, released August 26, 2026, had already been running on OpenRouter as an uncredited stealth model called "Ox Alpha" when Z.ai claimed it as a GLM release earlier that day. At 320B total parameters with 18B active it was a fraction of the size of the 743B GLM-5.3 that preceded it by twelve days, and Z.ai benchmarked it against GLM-5.2 rather than that model: it beat GLM-5.2 on all six tests in the launch chart, most heavily on AutomationBench at 48.8% and DeepSWE v1.1 at 63.4%. Its GDPval-AA v2 rating of 1773 topped the chart outright, ahead of the DeepSeek, Claude, GPT and Gemini entries set beside it. Elsewhere it sat mid-pack against those closed flagships — 84.3% on Terminal-Bench 2.1, 55.3% on Humanity's Last Exam with tools and 26.3% on Agent's Last Exam were all a few points short of the leaders at the time — and the much larger GLM-5.3 still led it on three of the shared tests. Two things made the release notable anyway. It was natively multimodal with a 1M-token context window and went out under the MIT License with weights on Hugging Face, a pointed contrast with GLM-5.3, which had launched through the GLM Coding Plan and ZCode with no weights at all. And Z.ai said it was trained entirely on Chinese AI chips, the first GLM release the lab made that claim for, which turned an open-weight launch into a data point about how far domestic silicon had come. Access opened the same day across the API, ZCode, chat.z.ai and AutoClaw. ## Questions and answers ### When was GLM-5.3-Flash released? GLM-5.3-Flash was released by Z.ai on Wednesday, Aug 26 2026. ### Who made GLM-5.3-Flash? GLM-5.3-Flash 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-5.3-Flash get? GLM-5.3-Flash reports 6 tracked benchmark scores — DeepSWE 1.1: 63.4%; Terminal-Bench 2.1: 84.3%; Humanity's Last Exam (with tools): 55.3%; Agent's Last Exam (pass@1): 26.3%; AutomationBench: 48.8%; GDPval-AA v2: 1773. Scores are the figures published at release by Z.ai. It holds the best score among all models tracked here on AutomationBench. ### What is the context window of GLM-5.3-Flash? GLM-5.3-Flash has a context window of 1M. That is the maximum amount of input plus output the model can hold in a single request. ### How many parameters does GLM-5.3-Flash have? GLM-5.3-Flash is reported at 320B parameters. ### Is GLM-5.3-Flash open source? Partly. GLM-5.3-Flash 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-5.3-Flash? Z.ai's previous tracked release was GLM-5.3 on Aug 14 2026, 12 days earlier. It is the most recent Z.ai model tracked on AI Release Tracker. --- Canonical page: https://aireleasetracker.com/model/zai/glm-5.3-flash Full dataset: https://aireleasetracker.com/llms-full.txt · JSON: https://aireleasetracker.com/models.json Source: AI Release Tracker (https://aireleasetracker.com). Benchmark scores are the figures published by the releasing lab at launch.