Z.ai's GLM-5.3-Flash was publicly revealed on August 26, 2026, confirmed by Bloomberg, as the anonymous "Ox Alpha" model that had topped OpenRouter and OpenCode usage charts for roughly a week with a 1M-token context window and text/image/video inputs. The model is a 320B-parameter mixture-of-experts with 18B active pe Weights landed on Hugging Face under an MIT license the same evening the identity was confirmed, and Zhipu's Hong Kong shares closed more than 12% higher the next day at roughly 10x January's IPO price. Stripe CEO Patrick Collison had called the still-anonymous model "very impressive" the day before the reveal, with St

Z.ai released GLM 5.3 Flash on August 26, 2026, under an MIT license on Hugging Face from day one, as a 320-billion-parameter mixture-of-experts activating 18B parameters per token. It is the first natively multimodal model in the GLM-5 series, built on a newly trained base rather than as a post-train of GLM-5.2, and s GLM 5.3 Flash was publicly confirmed as the identity of the anonymous "Ox Alpha" model that had been serving traffic on OpenRouter and drawing attention for its 1M-token context. Notably, GLM 5.3's own 744B weights remain unreleased — Z.ai's Hugging Face organisation has no GLM 5.3 repository — so Flash is the open-wei

Z.ai released GLM-5.3-Flash on August 26, 2026, as the newest member of the GLM-5 family, designed to deliver frontier-level capability without frontier-level inference cost. The model has 320 billion total parameters with about 18 billion active per token, supports multimodal inputs, offers a context window of up to 1 The Medium article frames the release as part of a broader shift in the AI model race where competition is about intelligence per unit of compute rather than raw parameter count. The piece reinforces that GLM-5.3-Flash is an open-weight release available to developers on launch day, with specs identical to those report

The ampere.sh comparison documents GLM 5.3 vs GLM 5.3 Flash specs explicitly: both developed by Z.ai, both released in August 2026 with a 1M-token context window, but GLM 5.3 is 753B total / 40B active while GLM 5.3 Flash is 320B / 18B active. Flash is natively multimodal and has public weights available, whereas GLM 5 The comparison also surfaces a counterintuitive finding: GLM 5.3 Flash is not actually faster at token generation despite the name, with Artificial Analysis measuring GLM 5.3 at roughly 85 tokens per second and Flash at about 49 tokens per second; Flash's time to first token is marginally faster at 1.46s vs 1.57s. Flas

Z.ai shipped GLM-5.3-Flash on August 26, 2026, as a 320B-parameter mixture-of-experts activating 18B per token, running natively in FP8 with a 1,048,576-token context window, and as the first natively multimodal model in the GLM-5 series. According to the Z.ai model card, it "starts from a newly trained base model, wit Weights ship under MIT on Hugging Face, the API is $0.15/$0.50 per million tokens, and the model beats GLM-5.2 across six coding and agentic benchmarks at roughly one-tenth of the price while approaching Claude Opus 4.8 on long-horizon agent tasks. For about a week before launch, the model was the anonymous "Ox Alpha"