GLM-5.3-Flash
GLM-5.3-Flash is Z.ai's first natively multimodal GLM-5 model: a 320B-parameter mixture-of-experts checkpoint with 18B active parameters, hybrid sparse and linear attention, and MIT-licensed weights.
Provider
Z.ai
Model family
Z.ai GLM
Open-weight multimodal MoE LLM
Cost tier
Flash
Status
Current
Release Aug 26, 2026
Why teams choose it
Z.ai says the model was previously previewed anonymously as ox-alpha on OpenCode and OpenRouter.
Official architecture notes 320B total / 18B active parameters
hybrid sparse plus linear attention, and about 1M-token long context.
This Flash SKU is distinct from hosted GLM-5.3: it is natively multimodal and ships MIT weights.
Tradeoffs to know
- Published coding, agent, and vision scores are vendor-reported and harness-sensitive.
- Self-hosting a 320B MoE still requires substantial GPU memory, a supported runtime, and quantization choices.
- List pricing, launch discounts, and Coding Plan quotas change; confirm current Z.ai terms before production use.
Technical specs
- Inputs
- text, image, video
- Outputs
- text
- Capabilities
- coding, agentic workflows, multimodal reasoning, visual coding, computer use, long-context, open-weight serving
- License
- MIT
- Source
- https://z.ai/blog/glm-5.3-flash
- Deep Swe V1 1
- 63.4
- Aa Intelligence Index
- 57
- Automationbench V1 0 6
- 48.8
Benchmarks
- Terminal Bench 2 1
- 84.3
- Toolathlon Verified
- 78.4
Z.ai GLM family lineup
Current models
Previous versions
Related models
GLM-5.3-Flash FAQ
What is GLM-5.3-Flash?
GLM-5.3-Flash is Z.ai's first natively multimodal GLM-5 model: a 320B-parameter mixture-of-experts checkpoint with 18B active parameters, hybrid sparse and linear attention, and MIT-licensed weights. Z.ai documents API access as glm-5.3-flash, Coding Plan and ZCode availability, and Hugging Face weights for SGLang, vLLM, and TokenSpeed.
When does GLM-5.3-Flash fit best?
Cost-sensitive coding agents
What should teams watch out for with GLM-5.3-Flash?
Published coding, agent, and vision scores are vendor-reported and harness-sensitive.
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