GLM-5.2 is probably the most powerful text-only open weights LLM
Chinese AI lab Z.ai released GLM-5.2 to their coding plan subscribers on June 13th, and then yesterday (June 16th) released the full open weights under an MIT license. Similar in size to their previous GLM-5 and GLM-5.1 releases, this is 753B parameter, 1.51TB monster - with 40 active parameters (Mixture of Experts). GLM-5.2 is a text input only model - Z.ai have a separate vision family most recently represented by GLM-5V-Turbo , but that one isn't open weights. GLM-5.2 has a 1 million token co
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GLM-5.2 is probably the most powerful text-only open weights LLM 17th June 2026 Chinese AI lab Z.ai released GLM-5.2 to their coding plan subscribers on June 13th, and then yesterday (June 16th) released the full open weights under an MIT license. Similar in size to their previous GLM-5 and GLM-5.1 releases, this is 753B parameter, 1.51TB monster—with 40 active parameters (Mixture of Experts). GLM-5.2 is a text input only model—Z.ai have a separate vision family most recently represented by GLM-5V-Turbo, but that one isn’t open weights. GLM-5.2 has a 1 million token context window, up from GLM-5.1’s 200,000. The buzz around this model is strong.
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Excerpt limited to ~120 words for fair-use compliance. The full article is at Simon Willison's Weblog.